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Publications dans les journaux scientifiques dans le domaine de l'ingénierie : 04-2017 trié par par titre, page: 0
» $L_{0}$ Gradient Projection
Résumé:
Minimizing L0 gradient, the number of the non-zero gradients of an image, together with a quadratic data-fidelity to an input image has been recognized as a powerful edge-preserving filtering method. However, the L0 gradient minimization has an inherent difficulty: a user-given parameter controlling the degree of flatness does not have a physical meaning since the parameter just balances the relative importance of the L0 gradient term to the quadratic data-fidelity term. As a result, the setting of the parameter is a troublesome work in the L0 gradient minimization. To circumvent the difficulty, we propose a new edge-preserving filtering method with a novel use of the L0 gradient. Our method is formulated as the minimization of the quadratic data-fidelity subject to the hard constraint that the L0 gradient is less than a user-given parameter α. This strategy is much more intuitive than the L0 gradient minimization because the parameter α has a clear meaning: the L0 gradient value of the output image itself, so that one can directly impose a desired degree of flatness by α. We also provide an efficient algorithm based on the so-called alternating direction method of multipliers for computing an approximate solution of the nonconvex problem, where we decompose it into two subproblems and derive closed-form solutions to them. The advantages of our method are demonstrated through extensive experiments.
Auteurs: Shunsuke Ono;
Apparue dans: IEEE Transactions on Image Processing
Date publication: 04.-2017, volume: 26, issue:4, pages: 1554 - 1564
Editeur: IEEE
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» $mathcal {H}$ Distribution for Multilook Polarimetric SAR Data
Résumé:
Polarimetric synthetic aperture radar (PolSAR) is an advanced imaging radar system, for which the acquired data provide not only the information of each channel but also the correlation between channels. To fully utilize and accurately model the multilook PolSAR data, a novel compound distribution, named the H distribution, is proposed based on the generalized Fisher distribution (GFD). Specifically, the GFD introduces a power parameter to the ordinary Fisher distribution. With one more free parameter, the GFD is flexible and versatile enough to characterize different kinds of texture. Then, by assuming the generalized-Fisher-distributed texture and the Wishart-distributed speckle, the H distribution is derived, whose closed-form expression is obtained with the help of Fox's H-function. As such, the H distribution has a compact form and is conveniently applied to practical problems, such as modeling and classification of PolSAR data. The effectiveness of this method is tested by modeling the multilook PolSAR data and performing image classification. The experimental results demonstrate that the H distribution is a flexible and effective way to model multilook PolSAR data.
Auteurs: Chi Liu;Heng-Chao Li;Xian Sun;William J. Emery;
Apparue dans: IEEE Geoscience and Remote Sensing Letters
Date publication: 04.-2017, volume: 14, issue:4, pages: 489 - 493
Editeur: IEEE
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» $mathcal {L}_{1}$ Adaptive Backstepping for Robust Trajectory Tracking of UAVs
Résumé:
This paper addresses the trajectory tracking control (i.e., outer-loop control) problem for unmanned aerial vehicles (UAVs) in the presence of modeling uncertainties and external disturbances. The kinematics and dynamics of the trajectory tracking problem are always in strict feedback form. While there is no uncertainty in the kinematics, rapidly changing uncertainties present in the dynamics makes this problem an ideal candidate for L1 adaptive backstepping control. The trajectory tracking controller serves as the outer-loop in a cascaded design architecture and supplies a reference quaternion and thrust to the inner-loop controller. The inner-loop controller in turn generates a moment demand for the control allocation module. Such an inner-outer loop architecture is modular and does away with the requirement that the commanded trajectory be four times differentiable as would be required if a single monolithic backstepping control law where to be used. Both simulations and flight tests are used to demonstrate the effectiveness of the proposed controller and how the controller tracks any twice differentiable trajectory, respectively.
Auteurs: Zongyu Zuo;Srinath Mallikarjunan;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 2944 - 2954
Editeur: IEEE
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» $V$ -Band High-Gain Printed Quasi-Parabolic Reflector Antenna With Beam-Steering
Résumé:
A novel design of printed ${V}$ -band quasi-parabolic reflector antenna is discussed. Two possible excitation methods are proposed which are used subsequently to design a more complex antenna with beam-steering capability. The radiation performance of the designed antenna is studied using full-wave simulations based on the finite-element method. The simulation results are verified experimentally.
Auteurs: Alister Hosseini;Saman Kabiri;Franco De Flaviis;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1589 - 1598
Editeur: IEEE
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» 0.2-THz Dual Mode Sheet Beam Traveling Wave Tube
Résumé:
Equipping the adjustable horizontal focusing electrodes (FEs), a dual mode electron gun providing different current beams, has been proposed and evaluated. Employing this tunable FE electron gun, a continuous wave (CW)/pulsed dual mode, 0.2-THz sheet beam traveling wave tube (SB-TWT) has been designed. The tube employs a high density and high current sheet beam for pulsed mode operation, and a reduced size and lower current sheet beam for the CW mode. This scheme provides CW mode increased efficiency and higher beam transmission factor than other, more conventional, dualmode techniques such as by changing the RF drive power. Using a 1.2-T uniform focusing magnetic field, both beams are predicted to have excellent transmission factor (more than 99%) to the collector through the 65-mm beam tunnel. Driven by the pulsed, high current electron beam, the 0.2-THz SB-TWT exhibits more than 100-W power over a 20-GHz bandwidth. Driven by the low current electron beam, the tube provides 20-dB gain and 10-W CW output power over the required bandwidth of 0.19 THz–0.21 THz.
Auteurs: Yuan Zheng;Diana Gamzina;Neville C. Luhmann;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 04.-2017, volume: 64, issue:4, pages: 1767 - 1773
Editeur: IEEE
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» 1-T Capacitorless DRAM Using Bandgap-Engineered Silicon-Germanium Bipolar I-MOS
Résumé:
In this paper, a 1-Transitor (1-T) capacitorless dynamic random access memory (DRAM) using bandgap-engineered silicon-germanium Bipolar ionization metal oxide semiconductor field effect transistor (I-MOS) is investigated through numerical simulations. We have demonstrated the application of the proposed Si0.6Ge0.4 Bipolar I-MOS for realization of a 1-T capacitorless DRAM. The proposed device can achieve hysteresis at significantly lower drain voltages ( V_{math\rm{LD}} =0.45 V to V_{math\rm{LU}} =1.15 V), in comparison to the inversion mode device ( V_{math\rm{LD}} = 8 V to V_{math\rm{LU}} =11 V). In addition, the proposed 1-T capacitorless DRAM exhibits a wider hysteresis window ( \Delta text{V} ) of the order ~700 mV and a sensing margin ( \Delta text{I} ) of ~5 orders in comparison to the inversion mode based 1-T capacitorless DRAM. Moreover, the proposed 1-T capacitorless DRAM exhibits the retention time of ~750 msec and ~320 msec for T = 25 °C and T = 85 °C, respectively. The proposed 1-T capacitorless DRAM also shows nondestructive read and an extreme long-term endurance. Therefore, the results presented in this paper can provide an opportunity for future DRAM design in deep nanometer technology.
Auteurs: Avinash Lahgere;Mamidala Jagadesh Kumar;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 04.-2017, volume: 64, issue:4, pages: 1583 - 1590
Editeur: IEEE
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» 10T SRAM Using Half- $V_{text {DD}}$ Precharge and Row-Wise Dynamically Powered Read Port for Low Switching Power and Ultralow RBL Leakage
Résumé:
We present, in this paper, a new 10T static random access memory cell having single ended decoupled read-bitline (RBL) with a 4T read port for low power operation and leakage reduction. The RBL is precharged at half the cell’s supply voltage, and is allowed to charge and discharge according to the stored data bit. An inverter, driven by the complementary data node (QB), connects the RBL to the virtual power rails through a transmission gate during the read operation. RBL increases toward the V_{text {DD}} level for a read-1, and discharges toward the ground level for a read-0. Virtual power rails have the same value of the RBL precharging level during the write and the hold mode, and are connected to true supply levels only during the read operation. Dynamic control of virtual rails substantially reduces the RBL leakage. The proposed 10T cell in a commercial 65 nm technology is 2.47\times the size of 6T with \beta = 2 , provides 2.3\times read static noise margin, and reduces the read power dissipation by 50% than that of 6T. The value of RBL leakage is reduced by more than 3 orders of magnitude and ({I_{math\rm{\scriptscriptstyle ON}}}/{I_{math\rm{\scriptscriptstyle OFF}}}) is greatly improved compared with the 6T BL leakage. The overall leakage characteristics of 6T and 10T are similar, and competitive performance is achieved.
Auteurs: Naeem Maroof;Bai-Sun Kong;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1193 - 1203
Editeur: IEEE
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» 2-D Unconditionally Stable CFS-PML Based on CNDG for Truncating Unmagnetized Plasma Media
Résumé:
An unconditionally stable implementation of the complex frequency-shifted perfectly matched layer based on Crank–Nicolson Douglas–Gunn (CNDG), combined the piecewise linear recursive convolution (PLRC) method is proposed to truncate the unmagnetized plasma in the finite-difference time-domain. The proposed algorithm makes full use of the unconditional stability of CNDG scheme and the high accuracy of the PLRC method. It not only saves much time and holds good absorbing performance, but is also easy to implement. A numerical example has been carried out to validate the algorithm.
Auteurs: Jianxiong Li;Xueyang Shi;Haolin Jiang;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 323 - 325
Editeur: IEEE
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» 2016 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications [Conference Reports]
Résumé:
Presents information on the 2016 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications.
Auteurs: Yong Fan;Yu Jian Cheng;Zi Xuan Huang;
Apparue dans: IEEE Microwave Magazine
Date publication: 04.-2017, volume: 18, issue:2, pages: 100 - 102
Editeur: IEEE
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» 2017 Top ten tech cars
Résumé:
You can show people an Italian supersedan that set a lap record on the famed Nurburgring circuit. You can point them to a sleek, affordable electric runabout that can go from Paris to Luxembourg on a single charge. But they'll probably just want to know one thing: When are cars going to drive themselves? The specter of the fully autonomous, virtually self-aware car has captured imaginations and dominated headlines like no other automotive story in decades. And for at least one very good reason: Such vehicles promise to dramatically reduce or even eliminate deaths and injuries in automobiles.
Auteurs: Lawrence Ulrich;
Apparue dans: IEEE Spectrum
Date publication: 04.-2017, volume: 54, issue:4, pages: 26 - 35
Editeur: IEEE
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» 3-bit Resistive RAM Write-Read Scheme Based on Complementary Switching Mechanism
Résumé:
While standard bipolar switching RRAM memory devices can be programmed into different resistance states, the complementary switching mechanism allows for two distinct switching locations that each can be programmed to these resistance states. In this letter, we present a technique to discriminate these switching locations and report on a novel scheme allowing for sub- \mu text{s} pulse write and read of eight different logic states in Pt/Ta2O5/Ta/Pt devices by using only four different resistive states. Thus, in addition to the multilevel capability of bipolar switching devices, double the information can be stored and read in a single complementary switching device.
Auteurs: A. Schönhals;J. Mohr;D. J. Wouters;R. Waser;S. Menzel;
Apparue dans: IEEE Electron Device Letters
Date publication: 04.-2017, volume: 38, issue:4, pages: 449 - 452
Editeur: IEEE
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» 3-D Antenna Radiation Pattern Reconstruction in a Reverberation Chamber Using Spherical Wave Decomposition
Résumé:
It has been shown that the correlation between the radiation patterns of two antennas can be measured in a reverberation chamber (RC). In this paper, it is shown that the self-correlation coefficient of an antenna, defined as the correlation between the radiation pattern of an antenna under test (AUT) and a transformed version of itself, can also be measured in an RC. It is found that the 3-D radiation pattern of the AUT can be reconstructed from the measured self-correlation coefficient by using spherical wave decomposition. Moreover, the axial ratio of the AUT can also be measured efficiently in the RC, when the pattern is directional. Numerical simulations and measurements in the RC and in an anechoic chamber have been undertaken. Good agreement is obtained, which confirms the validity of the proposed method. Thus, this novel method can become a very useful, cost-effective, and efficient method for 3-D antenna radiation pattern measurement.
Auteurs: Qian Xu;Yi Huang;Lei Xing;Chaoyun Song;Zhihao Tian;Saqer S. Alja’afreh;Manoj Stanley;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1728 - 1739
Editeur: IEEE
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» 3-D Application-Oriented Visual Correlation Model in Wireless Multimedia Sensor Networks
Résumé:
Wireless multimedia sensor networks comprise a large number of sensor devices and obtain multiple types data from field of interest. In a visual sensor network, there exist visual correlation (VC) characteristics among images observed by camera-equipped sensors with overlapped field of views. To describe the characteristics, the conventional method is based on image matching. However, it is too complex to be applied to resource-constrained cameras. In this paper, based on 3-D sensing model and spatial geometric transformation, a 3-D application-oriented VC (3-D-AOVC) model is designed to quantitatively describe the correlation characteristics according to the specific application requirement. Furthermore, a 3-D VC coefficient (3-D-VCC) algorithm, which is aimed at the measurement of data redundancy is provided to elaborate the process of 3-D-AOVC model. Finally, utilizing the data redundancy measured by provided 3-D-VCC algorithm, a VC-based distributed energy efficient (VCDEE) scheme is devised. Experimental results show that the 3-D-AOVC model can accurately model the VC characteristics and the VCC algorithm has lower computational complexity and energy consumption than existing algorithm. Further simulation results demonstrate that the VCDEE scheme outperforms the state of the art in terms of energy conservation and balance.
Auteurs: Xiaotao Yang;Yingyou Wen;Duoning Yuan;Mingyang Zhang;Hong Zhao;
Apparue dans: IEEE Sensors Journal
Date publication: 04.-2017, volume: 17, issue:8, pages: 2583 - 2595
Editeur: IEEE
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» 3-D-Printed Microwave and THz Devices Using Polymer Jetting Techniques
Résumé:
3-D additive manufacturing (AM) offers unprecedented flexibility in the realization of complicated 3-D structures. Polymer jetting is one of the promising 3-D AM techniques that utilizes photosensitive polymers as the build material and is capable of precisely printing electromagnetic (EM) components up into the THz range. In this paper, important design and implementation aspects of polymer-jetting-based 3-D-printed EM components are discussed. A number of 3-D-printable polymer materials and their broadband EM characterization from GHz to THz are introduced. Design methodologies specific for 3-D-printed antennas and other EM components are presented. As examples, various 3-D-printed devices operating from GHz to THz frequency, including electromagnetic crystals (EMXT), waveguide, horn antenna, gradient index (GRIN) lenses, as well as 3-D AM-enabled new designs, such as millimeter wave (mmW)/THz, reflect array antennas, computer-generated THz holograms, and so on are reviewed. Moreover, current limitations and possible future improvements of the polymer jetting technique for EM applications are discussed. This type of 3-D AM technique is likely to enable many novel antenna and circuit architectures as well as various interesting 3-D metamaterial structures.
Auteurs: Hao Xin;Min Liang;
Apparue dans: Proceedings of the IEEE
Date publication: 04.-2017, volume: 105, issue:4, pages: 737 - 755
Editeur: IEEE
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» 32 × 32-Bit 4-Bit Bit-Slice Integer Multiplier for RSFQ Microprocessors
Résumé:
A design of a 32 × 32-bit 4-bit bit-slice integer multiplier for rapid single-flux quantum microprocessors is shown. The multiplier carries out both signed and unsigned multiplication. It is designed with synchronous concurrent-flow clocking and target frequency of 50 GHz using the AIST 1.0-μm Nb/AlOx/Nb, nine-layer advanced process 2 fabrication technology with a critical current density of 10 kA/cm2. It consists of 56 885 Josephson junctions. The area is 12.00 × 6.65 mm2. The simulation results show correct operation with frequency of 50 GHz at the dc bias voltage of 2.5 mV. The throughput is 3.125 × 109 multiplications per second.
Auteurs: Guang-Ming Tang;Kazuyoshi Takagi;Naofumi Takagi;
Apparue dans: IEEE Transactions on Applied Superconductivity
Date publication: 04.-2017, volume: 27, issue:3, pages: 1 - 5
Editeur: IEEE
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» 3D Solid Texture Classification Using Locally-Oriented Wavelet Transforms
Résumé:
Many image acquisition techniques used in biomedical imaging, material analysis, and structural geology are capable of acquiring 3D solid images. Computational analysis of these images is complex but necessary, since it is difficult for humans to visualize and quantify their detailed 3D content. One of the most common methods to analyze 3D data is to characterize the volumetric texture patterns. Texture analysis generally consists of encoding the local organization of image scales and directions, which can be extremely diverse in 3D. Current state-of-the-art techniques face many challenges when working with 3D solid texture, where most approaches are not able to consistently characterize both scale and directional information. 3D Riesz–wavelets can deal with both properties. One key property of Riesz filterbanks is steerability, which can be used to locally align the filters and compare textures with arbitrary (local) orientations. This paper proposes and compares three novel local alignment criteria for higher-order 3D Riesz–wavelet transforms. The estimations of local texture orientations are based on higher-order extensions of regularized structure tensors. An experimental evaluation of the proposed methods for the classification of synthetic 3D solid textures with alterations (such as rotations and noise) demonstrated the importance of local directional information for robust and accurate solid texture recognition. These alignment methods achieved an accuracy of 0.95 in the rotated data, three times more than the unaligned Riesz descriptor that achieved 0.32. The accuracy obtained is better than all other techniques that are published and tested on the same database.
Auteurs: Yashin Dicente Cid;Henning Müller;Alexandra Platon;Pierre-Alexandre Poletti;Adrien Depeursinge;
Apparue dans: IEEE Transactions on Image Processing
Date publication: 04.-2017, volume: 26, issue:4, pages: 1899 - 1910
Editeur: IEEE
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» 4 m/100 Gb/s Optical Wireless Communication Based on Far L–Band Injection Locked Quantum-Dash Laser
Résumé:
An indoor 100 Gb/s free space optical communication link using an injection locked ~1621 nm quantum-dash laser has been experimentally demonstrated. The results are achieved using dual-polarization quadrature phase shift keying (DP-QPSK) and coherent detection over a 4 m indoor free space link. The system exhibited a receiver sensitivity of -17.5 dBm to achieve the bit error rate forward error correction (BER FEC) threshold of 3.8 × 10-3. This displays the potential of tunable injection locked far L -band quantum-dash lasers, with less scattering loss compared to C-band counterpart, as promising light sources in both indoor and outdoor future high speed free space optical information and communication technology.
Auteurs: Muhammad Talal Ali Khan;Mohamed Adel Shemis;Amr Mohamed Ragheb;Maged Abdullah Esmail;Habib Ali Fathallah;Saleh Alshebeili;Mohammed Zahed Mustafa Khan;
Apparue dans: IEEE Photonics Journal
Date publication: 04.-2017, volume: 9, issue:2, pages: 1 - 7
Editeur: IEEE
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» 4H-SiC Ultraviolet Avalanche Photodiodes With Small Gain Slope and Enhanced Fill Factor
Résumé:
In this paper, 4H-SiC separated absorption charge and multiplication ultraviolet avalanche photodiodes (APDs) with small gain-voltage slope and enhanced fill factor are designed and fabricated. As a special reach-through structure, the absorption layer of the APD is fully depleted at breakdown voltage, which can share a considerable portion of reverse bias. As a result, the sensitivity of electric field within the multiplication layer as a function of overbias is reduced, leading to a small gain slope. Given the fact that the impact ionization coefficient of holes is less sensitive to electric field variation than that of electrons, the APD is also designed to be a hole-initiated ionization type, which can further reduce the gain slope. Meanwhile, three different top-electrode geometric patterns of SiC APDs are designed, and their impact on APD performance is investigated for the first time. Severe current crowding effect is observed in the forward current–voltage (I–V) characteristics of the APD with a traditional dot top-electrode, indicating inefficient current spreading across the top contact layer due to nonnegligible lateral resistance. In contrast, the forward I–V characteristics and photo-current at the avalanche regime of the APDs with optimized branch-shaped top-electrodes are apparently improved, owing to the improvement of electric field distribution and avalanche multiplication uniformity across the device active area. Furthermore, photon count rate increases by two to four times with larger voltage pulse height, suggesting enhanced effective avalanche multiplication area and fill factor.
Auteurs: Sen Yang;Dong Zhou;Weizong Xu;Xiaolong Cai;Hai Lu;Dunjun Chen;Fangfang Ren;Rong Zhang;Youdou Zheng;
Apparue dans: IEEE Photonics Journal
Date publication: 04.-2017, volume: 9, issue:2, pages: 1 - 8
Editeur: IEEE
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» 60-GHz Millimeter-Wave Channel Measurements and Modeling for Indoor Office Environments
Résumé:
The millimeter-wave (mmWave) band will be used for the fifth-generation communication systems. In this paper, 60-GHz mmWave channel measurements and modeling are carried out for indoor office environments. The rotated directional antenna-based method and uniform virtual array-based method are adopted and compared to investigate the 60-GHz channel in a 3-D space, simultaneously covering azimuth and coelevation domains. The multipath component parameters including power, delay, azimuth, and elevation angles are estimated with the space-alternating generalized expectation–maximization estimation algorithm, and then processed with the K-means clustering algorithm. An extended Saleh–Valenzuela model with both delay and angular cluster features is used to characterize the measured channel, and the intercluster and intracluster parameters are extracted. We find that the azimuth departure angles are diverse and highly related to the antenna position and measurement environment, while the elevation departure angles are more related to the antenna height difference and confined in a relatively small direction range. The azimuth angle spread is much larger than the elevation angle spread either in global level or in cluster level. The results agree with the studies in the literature and channel models in IEEE standards.
Auteurs: Xianyue Wu;Cheng-Xiang Wang;Jian Sun;Jie Huang;Rui Feng;Yang Yang;Xiaohu Ge;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1912 - 1924
Editeur: IEEE
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» 70W GaN-HEMT Ku-Band Power Amplifier in MIC Technology
Résumé:
In this paper the design, implementation, and experimental results of a Ku-band 70W GaN-HEMT power amplifier (PA) for satellite communication are presented. A two-stage design approach with two 250nm bare-die devices has been chosen to achieve a considerably high saturated gain of 15 dB over the whole extended Ku-band (13.75–14.5 GHz). The circuit was realized in a hybrid microwave integrated circuit technology on an alumina substrate. The PA shows a measured performance of more than 50W output power for a continuous-wave signal with a power-added efficiency (PAE) higher than 23%. Modulated measurements demonstrate an average output power of more than 30W (70W peak) and 21% PAE, while holding the Eutelsat linearity requirements.
Auteurs: Daniel Maassen;Felix Rautschke;Florian Ohnimus;Lothar Schenk;Uwe Dalisda;Georg Boeck;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 04.-2017, volume: 65, issue:4, pages: 1272 - 1283
Editeur: IEEE
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» 8.3 M-Pixel 480-fps Global-Shutter CMOS Image Sensor with Gain-Adaptive Column ADCs and Chip-on-Chip Stacked Integration
Résumé:
This paper presents a 4K2K 480-fps global-shutter CMOS image sensor with a super 35-mm format for a highly realistic digital video system. The sensor employs newly developed gain-adaptive column analog-to-digital converters to obtain input-referred dark random noise of 140 $mu text{V}_{mathrm {rms}}$ for an input-referred full-scale readout of 923 mV. An on-chip online correction of the error between two switchable gains maintained the nonlinearity of the output image within 0.18%. A chip-on-chip integration process realized a front-illuminated image sensor stacked with two diced logic chips through 38-K microbump interconnections. The global-shutter pixel achieved a parasitic light sensitivity of −99.6 dB. The 16-channel output interfaces with 4.752 Gbps/ch were implemented in the stacked logic chips.
Auteurs: Yusuke Oike;Kentaro Akiyama;Luong D. Hung;Wataru Niitsuma;Akihiko Kato;Mamoru Sato;Yuri Kato;Wataru Nakamura;Hiroshi Shiroshita;Yorito Sakano;Yoshiaki Kitano;Takuya Nakamura;Takayuki Toyama;Hayato Iwamoto;Takayuki Ezaki;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 985 - 993
Editeur: IEEE
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» A $k$ -Space Pseudospectral Method for Elastic Wave Propagation in Heterogeneous Anisotropic Media
Résumé:
This paper presents the theory of the $k$ -space method generalized to model elastic wave propagation in heterogeneous anisotropic media. The $k$ -space methods are promising time integration techniques giving, in conjunction with collocation spectral methods, accurate and efficient numerical schemes for problems in heterogeneous media. In this paper, the $k$ -space operator is derived in a spatially continuous form using the Fourier analysis of the displacement formalism of elastodynamics. An efficient numerical algorithm is then constructed by applying a Fourier collocation spectral method, leading to define the discrete $k$ -space scheme. The proposed method is temporally exact for homogeneous media, unconditionally stable for heterogeneous media, and also allows larger time steps without loss of accuracy. Implementation of the method is discussed in detail. The method is validated through a set of numerical tests. The numerical results show the efficacy of the method compared with the conventional schemes.
Auteurs: Kamyar Firouzi;Butrus T. Khuri-Yakub;
Apparue dans: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Date publication: 04.-2017, volume: 64, issue:4, pages: 749 - 760
Editeur: IEEE
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» A ±36-A Integrated Current-Sensing System With a 0.3% Gain Error and a 400- $mu text{A}$ Offset From −55 °C to +85 °C
Résumé:
This paper presents an integrated shunt-based current-sensing system (CSS) capable of handling ±36-A currents, the highest ever reported. It also achieves a 0.3% gain error and a 400- $mu text{A}$ offset, which is significantly better than the state-of-the-art systems. The heart of the system is a robust 260- $mu Omega $ shunt resistor made from the lead frame of a standard HVQFN plastic package. The resulting voltage drop is then digitized by a precision $Delta Sigma $ ADC and a bandgap reference (BGR). At the expense of current handling capability, a ±5-A version of the CSS uses a 10- $text{m}Omega $ on-chip metal shunt to achieve just a 4- $mu text{A}$ offset. Both designs are realized in a standard 0.13- $mu text{m}$ CMOS process and draw 13 $mu text{A}$ from a 1.5-V supply. Compensation of the spread and nonlinear temperature dependency of the shunt resistor $R_{mathrm {shunt}}$ is accomplished by the use of a fixed polynomial master curve and a single room temperature calibration. This procedure also effectively compensates for the residual spread and nonlinearity of the ADC and the BGR.
Auteurs: Saleh Heidary Shalmany;Dieter Draxelmayr;Kofi A. A. Makinwa;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1034 - 1043
Editeur: IEEE
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» A ± 3 ppm/°C Single-Trim Switched Capacitor Bandgap Reference for Battery Monitoring Applications
Résumé:
A precision bandgap reference has been developed in a $0.18~mu text {m}$ BiCMOS process that achieves ±3 ppm/°C temperature drift at ±3 $sigma $ from −40 °C to 110 °C. The reference is designed to utilize single temperature trim and standard components. A 3.65 V switched capacitor reference voltage is provided to a $2^{{textrm {nd}}}$ order delta-sigma modulator ADC to digitize a battery cell voltage. The switched capacitor reference utilizes fully differential sampling which reduces the errors from channel charge injection and clock feedthrough introduced by pseudo-differential sampling. A new technique for sampling a $text {V}_{{textrm {be}}}$ voltage directly onto the output of the reference’s differential amplifier has been developed that removes the error that would be introduced from differentially sampling the $text {V}_{{textrm {be}}}$ and the $Delta text {V}_{{textrm {be}}}$ voltage terms independently. The bandgap reference and ADC combination have an input referred noise spectral density of $4.7~mu text {V}/surd $ Hz from 0.1 to 162 Hz yielding 15 stable output bits.
Auteurs: Bradford L. Hunter;Wallace E. Matthews;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 777 - 786
Editeur: IEEE
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» A —244-dB FOM High-Frequency Piezoelectric Resonator-Based Cascaded Fractional-N PLL With Sub-ppb-Order Channel-Adjusting Technique
Résumé:
This paper proposes a cascaded fractional-N phase-locked loop (PLL) based on a high-frequency piezoelectric resonator (PZR). Sub-ppb-order frequency resolution is achieved by a channel adjustment technique. Besides its small form factor, a high- ${Q}$ PZR at gigahertz frequencies realizes a very low phase-noise synthesizer for RF applications. However, three fundamental issues remain to be solved: the narrow tuning range and large process variation of PZR-based oscillators, the low-frequency resolution of a PLL referenced to gigahertz-order frequencies, and the undesirable harmonic oscillation caused by the inductance of the CMOS-PZR bonding wire. To overcome these issues, we propose a channel-adjusting technique (CAT) that adaptively sets the division ratio of two PLLs to maintain constant output frequency of the second PLL while varying the PZR oscillator frequency, hence permitting the narrow tuning range and wide process variation of the PZR oscillator. The first PLL in our PLL architecture determines the output frequency resolution and the second reduces the power consumption of the delta–sigma modulator. We also suppress the harmonic oscillations in the PZR oscillator. The prototype PLL is fabricated in a 65-nm CMOS and achieves an 8.484–8.912-GHz output, 180-fs rms jitter, and −244-dB FOM while consuming 12.7-mW power. We developed a cascaded fractional-N PLL based on a high-frequency PZR with a sub-ppb-order CAT, which overcomes the narrow tuning range problem in gigahertz PZRs. A prototype PLL fabricated in a 65-nm CMOS consumed 12.7 mWand output 8.484–8.912 GHz with 180-fs rms jitter.
Auteurs: Sho Ikeda;Hiroyuki Ito;Akifumi Kasamatsu;Yosuke Ishikawa;Takayoshi Obara;Naoki Noguchi;Koji Kamisuki;Yao Jiyang;Shinsuke Hara;Dong Ruibing;Shiro Dosho;Noboru Ishihara;Kazuya Masu;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1123 - 1133
Editeur: IEEE
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» A 0.13- $mu text{m}$ CMOS Dynamically Reconfigurable Charge Pump for Electrostatic MEMS Actuation
Résumé:
An eight-stage reconfigurable charge pump for microelectromechanical system (MEMS) electrostatic actuation was designed and fabricated in a standard 0.13- \mu text{m} CMOS technology. The purpose of the circuit is to generate sufficient on-chip voltages that are continually reconfigurable for MEMS actuation. Small 1-pF pumping capacitors are used to reduce the circuit area. Digitally programmable voltage levels can be outputted by varying the number of stages and the clock drive levels dynamically. Reduced power consumption is achieved using a variable frequency clock. The circuit attains a measured maximum output voltage of 10.1 V from a 1.2 V supply. Its nominal clock is set to 50 MHz. The circuit has a compact area of 215 \mu text {m} \times 300~\mu text{m} and consumes 864 \mu text{W} at a 50-MHz clock and 252 \mu text{W} at an 8-MHz clock.
Auteurs: Abdul Hafiz Alameh;Frederic Nabki;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1261 - 1270
Editeur: IEEE
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» A 0.23- $mu text{g}$ Bias Instability and 1- $mu text{g}/surd $ Hz Acceleration Noise Density Silicon Oscillating Accelerometer With Embedded Frequency-to-Digital Converter in PLL
Résumé:
This paper presents a silicon oscillating accelerometer (SOA) with a new CMOS readout circuit architecture. A phase lock loop (PLL) with a hybrid and antinoise folding PFD is employed to sustain the oscillation of the MEMS oscillator, and the oscillation amplitude is set by an external reference. In addition, a sigma-delta frequency-to-digital converter is combined with the PLL to digitize the accelerometer’s frequency output for low power consumption. The MEMS transducer and the readout circuit are fabricated in an 80- $mu text{m}$ SOI and standard 0.35- $mu text{m}$ CMOS process, respectively. The SOA achieves 0.23- $mu text{g}$ bias instability and 1- $mu text{g}$ /Hz $^{1/2}$ acceleration noise density with a ±30 g full-scale, which are equivalent to 4-ppb relative instability and 17-ppb/Hz $^{1/2}$ relative acceleration noise density. It only consumes 2.7 mW under a 1.5 V supply.
Auteurs: Jian Zhao;Xi Wang;Yang Zhao;Guo Ming Xia;An Ping Qiu;Yan Su;Yong Ping Xu;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1053 - 1065
Editeur: IEEE
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» A 0.3–15 GHz SiGe LNA With >1 THz Gain-Bandwidth Product
Résumé:
A wideband LNA with a frequency range of 0.3–15 GHz is introduced for space-based applications. The LNA achieves less than 2.2 dB noise figure (NF) at room temperature, with minimum measured NF of 1.8 dB and peak gain of 37.3 dB. To the authors’ best knowledge, this is the lowest NF at this bandwidth, with the highest gain-bandwidth product (1.1 THz) reported to date. Moreover, the performance of the LNA was studied across temperature, down to 78 K. The NF improves considerably and achieves a record average value of 1 dB over the whole bandwidth at 78 K, with a minimum NF of 0.74 dB at 1 GHz. Additionally, the bandwidth and gain were enhanced at 78 K without degrading input or output matching. To compensate for small gain variations across temperature, a gain control technique is proposed, which yields more than 15 dB of gain control without breaking the feedback loop and without sacrificing power matching.
Auteurs: Saeed Zeinolabedinzadeh;A. Çagri Ulusoy;Michael A. Oakley;Nelson E. Lourenco;John D. Cressler;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 380 - 382
Editeur: IEEE
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» A 0.35-V 520- $mu text{W}$ 2.4-GHz Current-Bleeding Mixer With Inductive-Gate and Forward-Body Bias, Achieving >13-dB Conversion Gain and >55-dB Port-to-Port Isolation
Résumé:
An ultralow voltage micropower 2.4-GHz current-bleeding active mixer for energy-harvesting Bluetooth low energy/ZigBee applications is reported. It features a double-balanced mixer topology combining nMOS current-bleeding transistors with a pMOS local oscillator switching quad, and forward-body bias and inductive-gate bias techniques to secure an adequate performance at a supply voltage down to 0.35 V. Fabricated in 0.13- $mu text{m}$ CMOS, the prototype exhibits a conversion gain of 13.77 dB, a third-order intercept point of −3.5 dBm, and a noise figure of 18 dB. The power consumption is $520~mu text{W}$ , and port-to-port isolation is >55 dB. The achieved figure of merit compares favorably with the state of the art.
Auteurs: Gim Heng Tan;Harikrishnan Ramiah;Pui-In Mak;Rui P. Martins;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 04.-2017, volume: 65, issue:4, pages: 1284 - 1293
Editeur: IEEE
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» A 0.4% PAE 194-GHz Signal Source With 1.5-mW Output Power in 65-nm Bulk CMOS Technology
Résumé:
This letter presents an amplifier-frequency doubler chain in thin digital 65-nm bulk CMOS process. Injection locking is applied to the amplifier to increase the power gain and compensate for the conversion loss in the frequency doubler. The doubler uses a compact low-impedance transmission line (LZ TLine) for effective dc decoupling in the output matching network. Measurement results show a peak output power of 1.5 mW at 194 GHz, and a peak PAE of 0.4% at 196 GHz. The locking range is measured as 8.5 GHz (92.5~101 GHz) with 2-dBm input fundamental power, and can be extended to 15 GHz with 4-dBm input power.
Auteurs: Kefei Wu;Sriram Muralidharan;Mona M. Hella;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 407 - 409
Editeur: IEEE
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» A 0.4-V Supply Curvature-Corrected Reference Generator With 84.5-ppm/°C Average Temperature Coefficient Within −40 °C to 130 °C
Résumé:
This brief describes a low-power current-mode voltage reference based on subthreshold transistors. A novel circuit configuration together with a high-order temperature compensation scheme allow this voltage reference to operate with a supply voltage down to 0.4 V over a large temperature range (from −40 °C to 130 °C). The circuit, which is fabricated with a standard 0.18- $mutext{m}$ CMOS technology, provides an output voltage of 212 mV, while consuming 192 nW. The measured average temperature coefficient is 84.5 ppm/°C.
Auteurs: Pinar Basak Basyurt;Edoardo Bonizzoni;Devrim Yilmaz Aksin;Franco Maloberti;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 362 - 366
Editeur: IEEE
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» A 0.45 V 147–375 nW ECG Compression Processor With Wavelet Shrinkage and Adaptive Temporal Decimation Architectures
Résumé:
This paper presents a real-time electrocardiogram (ECG) data compression processor with improved energy efficiency while maintaining high accuracy and real-time operation. Wavelet shrinkage is exploited to filter the noise and achieve sparse ECG signal representation. Adaptive temporal decimation is proposed to achieve configurable processing to adaptively reduce the data amount and computational activities for further power reduction. Modified Huffman and run-length wavelet source coding (MHRLC) is also designed to represent wavelet coefficients with optimized average code length and reduced memory requirement. Fabricated in 0.18- \mu text{m} CMOS, the ECG processor is implemented with customized near-threshold digital logics for minimum energy operation. The prototype was fully validated with the MIT-BIH Arrhythmia database. With a power consumption of 147–375 nW at 0.45 V, the proposed ECG processor exhibits a wide compression ratio ranging from 2.89 to 26.91, corresponding to a percentage-RMS-distortion from 0% to 3.11%.
Auteurs: Chio-In Ieong;Mingzhong Li;Man-Kay Law;Pui-In Mak;Mang I Vai;Rui P. Martins;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1307 - 1319
Editeur: IEEE
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» A 0.9-μm² 1T1R Bit Cell in 14-nm High-Density Metal Fuse Technology for High-Volume Manufacturing and In-Field Programming
Résumé:
This paper introduces the first high-volume manufacturable (HVM) metal-fuse technology in a 14-nm trigate high-k metal-gate CMOS process. A high-density array featuring a 0.9-μm² bit cell with an efficient bit level redundancy scheme is presented. An array efficiency of over 53% is achieved through hierarchical bitline design by minimizing the impact of parasitic resistance on fuse programming through short local bitline and sharing sense amplifier through longer global bitline. A power gating-based scheme is adopted to reduce leakage current consumption and high-voltage exposure to minimize reliability concern. Program conditions can be optimized for HVM and in-field programming to achieve close to 100% unit level yield with the proposed redundancy scheme.
Auteurs: Zhanping Chen;Sarvesh H. Kulkarni;Vincent E. Dorgan;Salil Manohar Rajarshi;Lei Jiang;Uddalak Bhattacharya;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 933 - 939
Editeur: IEEE
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» A 10-b Fourth-Order Quadrature Bandpass Continuous-Time $Sigma Delta $ Modulator With 33-MHz Bandwidth for a Dual-Channel GNSS Receiver
Résumé:
A fourth-order quadrature bandpass continuous-time sigma–delta modulator for a dual-channel global navigation satellite system (GNSS) receiver is presented. With a bandwidth (BW) of 33 MHz, the modulator is able to digitalize the downconverted GNSS signals in two adjacent signal bands simultaneously, realizing dual-channel GNSS reception with one receiver channel instead of two independent receiver channels. To maintain the loop-stability of the high-order architecture, any extra loop phase shifting should be minimized. In the system architecture, a feedback and feedforward hybrid architecture is used to implement the fourth-order loop-filter, and a return-to-zero (RZ) feedback after the discrete-time differential operation is introduced into the input of the final integrator to realize the excess loop delay compensation, saving a spare summing amplifier. In the circuit implementation, power-efficient amplifiers with high-frequency active feedforward and antipole-splitting techniques are employed in the active RC integrators, and self-calibrated comparators are used to implement the low-power 3-b quantizers. These power saving techniques help achieve superior figure of merit for the presented modulator. With a sampling rate of 460 MHz, current-steering digital–analog converters are chosen to guarantee high conversion speed. Implemented in only 180-nm CMOS, the modulator achieves 62.1-dB peak signal to noise and distortion ratio, 64-dB dynamic range, and 59.3-dB image rejection ratio, with a BW of 33 MHz, and consumes 54.4 mW from a 1.8 V power supply.
Auteurs: Junfeng Zhang;Yang Xu;Zehong Zhang;Yichuang Sun;Zhihua Wang;Baoyong Chi;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 04.-2017, volume: 65, issue:4, pages: 1303 - 1314
Editeur: IEEE
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» A 13.5–19 GHz 20.6-dB Gain CMOS Power Amplifier for FMCW Radar Application
Résumé:
A Ku-band wideband power amplifier (PA) for frequency modulated continuous wave (FMCW) radar application is proposed and implemented in 65-nm bulk CMOS technology. To obtain low group delay, low amplitude ripple, and wide bandwidth, the transformer and inductor-based matching network is designed to meet the requirements. Including pads, the PA occupies a compact chip area of 0.62 mm2. Consuming 118-mA current from 1.2-V power supply, it demonstrates output saturation power of 13.9 dBm. The measured 3-dB bandwidth is 5.5 GHz with maximum gain of 20.65 dB at 15.5 GHz. Finally, the PA is integrated with an FMCW signal generator to constitute an FMCW radar transmitter. The amplitude ripple of this chirp signal is less than 2 dB, and the output power is larger than 9 dBm through a bonding wire and a transmission line on printed circuit board.
Auteurs: Bo Chen;Liheng Lou;Kai Tang;Yong Wang;Jianjun Gao;Yuanjin Zheng;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 377 - 379
Editeur: IEEE
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» A 16 b Multi-Step Incremental Analog-to-Digital Converter With Single-Opamp Multi-Slope Extended Counting
Résumé:
This paper presents a multi-step incremental analog-to-digital converter (IADC) using multi-slope extended counting. Only one active integrator is used in the three-step conversion cycle. The accuracy of the IADC is extended by having it configured asmulti-slope ADCs in two additional steps. The proposed IADC uses the same circuitry as a first-order IADC (IADC1), but it exhibits better performance than a second-order IADC. For the same accuracy, the conversion cycle is shortened by a large factor (by more than 29 for the implemented device) compared with that of a conventional single-step IADC1. Fabricated in 0.18 $mu text{m}$ CMOS process, the prototype ADC occupies 0.5 mm2. With a 642 kHz clock, it achieves an SNDR of 52.2 dB in the first step. The SNDR is boosted to 79.8 dB in the second step and to 96.8 dB in the third step, over a 1 kHz signal band. The power consumption is 35 $mu text{W}$ from a 1.5 V power supply. This gives an excellent Schreier figure of merit of 174.6 dB.
Auteurs: Yi Zhang;Chia-Hung Chen;Tao He;Gabor C. Temes;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1066 - 1076
Editeur: IEEE
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» A 16-Core Voltage-Stacked System With Adaptive Clocking and an Integrated Switched-Capacitor DC–DC Converter
Résumé:
This paper presents a 16-core voltage-stacked system with adaptive frequency clocking (AFClk) and a fully integrated voltage regulator that demonstrates efficient on-chip power delivery for multicore systems. Voltage stacking alleviates power delivery inefficiencies due to off-chip parasitics but adds complexity to combat internal voltage noise. To address the corresponding issue of internal voltage noise, the system utilizes an AFClk scheme with an efficient switched-capacitor dc–dc converter to mitigate noise on the stack layers and to improve system performance and efficiency. Experimental results demonstrate robust voltage noise mitigation as well as the potential of voltage stacking as a highly efficient power delivery scheme. This paper also illustrates that augmenting the hardware techniques with intelligent workload allocation that exploits the inherent properties of voltage stacking can preemptively reduce the interlayer activity mismatch and improve system efficiency.
Auteurs: Sae Kyu Lee;Tao Tong;Xuan Zhang;David Brooks;Gu-Yeon Wei;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1271 - 1284
Editeur: IEEE
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» A 16-Gb/s 14.7-mW Tri-Band Cognitive Serial Link Transmitter With Forwarded Clock to Enable PAM-16/256-QAM and Channel Response Detection
Résumé:
A cognitive tri-band transmitter (TX) with a forwarded clock using multiband signaling and high-order digital signal modulations is presented for serial link applications. The TX features learning an arbitrary channel response by sending a sweep of continuous wave, detecting power level at the receiver side, and then adapting modulation scheme, data bandwidth, and carrier frequencies accordingly based on detected channel information. The supported modulation scheme ranges from nonreturn to zero/Quadrature phase shift keying (QPSK) to Pulse-amplitude modulation (PAM) 16/256-Quadrature amplitude modulation(QAM). The proposed highly reconfigurable TX is capable of dealing with low-cost serial channels, such as low-cost connectors, cables, or multidrop buses with deep and narrow notches in the frequency domain (e.g., a 40-dB loss at notches). The adaptive multiband scheme mitigates equalization requirements and enhances the energy efficiency by avoiding frequency notches and utilizing the maximum available signal-to-noise ratio and channel bandwidth. The implemented TX prototype consumes a 14.7-mW power and occupies 0.016 mm2 in a 28-nm CMOS. It achieves a maximum data rate of 16 Gb/s with forwarded clock through one differential pair and the most energy efficient figure of merit of 20.4 $mu text{W}$ /Gb/s/dB, which is calculated based on power consumption of transmitting per gigabits per second data and simultaneously overcoming per decibel worst case channel loss within the Nyquist frequency.
Auteurs: Yuan Du;Wei-Han Cho;Po-Tsang Huang;Yilei Li;Chien-Heng Wong;Jieqiong Du;Yanghyo Kim;Boyu Hu;Li Du;Chunchen Liu;Sheau Jiung Lee;Mau-Chung Frank Chang;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1111 - 1122
Editeur: IEEE
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» A 17 mW 3-to-5 GHz Duty-Cycled Vital Sign Detection Radar Transceiver With Frequency Hopping and Time-Domain Oversampling
Résumé:
This paper presents a low power interference-robust radar transceiver architecture for noncontact vital sign detection and mobile healthcare applications. A duty-cycled transceiver design is proposed to significantly reduce power consumption of front-end circuits. Occupying 3-to-5 GHz band with four 500 MHz sub-channels, the radar mitigates the narrowband interference (NBI) problem with the frequency hopping scheme. In the time domain, the $Delta Sigma $ TDC is employed to achieve fine ranging resolution with noise shaped oversampling. The transceiver implemented in 65 nm CMOS consumes 17.2 mW from a 1.0-V supply when duty-cycled and achieves an RMS detection accuracy of 5.68 mm.
Auteurs: Xican Chen;Yiyu Shen;Zhicheng Wang;Woogeun Rhee;Zhihua Wang;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 969 - 980
Editeur: IEEE
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» A 2.048 Mb/s Full-Duplex Free-Space Optical Transceiver IC for a Real-Time In Vivo Brain–Computer Interface Mouse Experiment Under Social Interaction
Résumé:
This paper presents the first free-space optical transceiver IC for social, psychological brain–computer interface experiments with multiple mice. The proposed IC embedded in a head-mounted module (HMM) includes 8-channel neural recorder and a neural stimulator in order to record extracellular action potentials and local field potentials while injecting diverse waveforms of monophasic intracranial stimulation current into the medial forebrain bundle for the activation of the nervous system. The HMM implanted on a mouse transmits the neural recording data to an optical base station by using a mandatory 591/624-nm (amber/red) visible behavior tracking LED as an optical transmitter to save power. The HMM is controlled simultaneously via a 940 nm infrared optical downlink to reduce interference to the visible optical uplink. The proposed IC fabricated in a 0.18- $mu text{m}$ HV BCDMOS process consumes 90 $mu text{W}$ while achieving a 2.048-Mb/s transmission rate.
Auteurs: Gunpil Hwang;Jong-Kwan Choi;Jaehyeok Yang;Sungmin Lim;Jae-Myoung Kim;Min-Gyu Choi;Kiuk Gwak;Jinwoo Jeon;Il-Hwan Choi;Sol Park;Dae-Shik Kim;Hee Sup Shin;Hyeon-Min Bae;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1007 - 1020
Editeur: IEEE
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» A 2.25–2.7 GHz Area-Efficient Subharmonically Injection-Locked Fractional-N Frequency Synthesizer With a Fast-Converging Correlation Loop
Résumé:
An area-efficient subharmonically injection-locked fractional-N frequency synthesizer is presented. The phase domain analysis confirms that a second-order subharmonically injection-locked phase-locked loop (SIPLL) can be stable even if the loop filter is composed of only a tiny capacitor. Thus, the area of the loop filter shrinks dramatically to realize an area-efficient SIPLL. Besides, a fast-converging correlation loop is used to calibrate the gain error of the digital-to-time converter in background by using a binary search algorithm. It ensures the initial output of the correlator close to the final one and is insensitive to process/supply/temperature variations. The chip is fabricated in a 40 nm process and occupies a core area of 0.0104 mm2. The converging time of the correlation loop is within $30~mu text {s}$ . The power consumption is 3.19 mW from a 1.1 V supply.
Auteurs: Yen-Hsiang Tseng;Che-Wei Yeh;Shen-Iuan Liu;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 811 - 822
Editeur: IEEE
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» A 2.3-mW 0.01-mm $^{text{2}}$ 1.25-GHz Quadrature Signal Corrector With 1.1-ps Error for Mobile DRAM Interface in 65-nm CMOS
Résumé:
In this brief, we propose a quadrature signal corrector for a low-power DDR4 mobile DRAM interface. In order to eliminate the phase imbalance among quadrature signals, the proposed architecture employs digitally controlled delay lines in a shared digital feedback loop with a time-multiplexed loop filter so as to minimize the effect of circuit mismatch that hampers the phase accuracy. A self-calibrated offset delay is also proposed, which allows the use of a simple 1-bit TDC instead of a power-hungry wide-dynamic range TDC. Implemented in 65-nm CMOS, the prototype chip achieves less than 1.1-ps phase error for a 1.25-GHz quadrature signal and occupies an active area of only 0.01 mm2 while consuming 2.27 mW from a 1.0-V supply.
Auteurs: YongJo Kim;Keunsoo Song;Dongkyun Kim;SeongHwan Cho;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 397 - 401
Editeur: IEEE
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» A 2.5 mW/ch, 50 Mcps, 10-Analog Channel, Adaptively Biased Read-Out Front-End IC With Low Intrinsic Timing Resolution for Single-Photon Time-of-Flight PET Applications With Time-Dependent Noise Analysis in 90 nm CMOS
Résumé:
This paper presents a 10-channel time-of-flight application-specific integrated circuit (ASIC) for positron emission tomography in a 90 nm standard CMOS process. To overcome variations in channel-to-channel timing resolution caused by mismatch and process variations, adaptive biases and a digital-to-analog converter (DAC) are utilized. The main contributions of this work are as follows. First, multistage architectures reduce the total power consumption, and detection bandwidths of analog preamplifiers and comparators are increased to 1 and 1.5 GHz, respectively, relative to those in previous studies. Second, a total intrinsic electronic timing resolution of 9.71 ps root-mean-square (RMS) is achieved (13.88 ps peak and 11.8 ps average of the 10 channels in 5 ASICs). Third, the proposed architecture reduces variations in channel-to-channel timing resolution to 2.6 bits (equivalent to 4.17 ps RMS) by calibrating analog comparator threshold levels. A 181.5 ps full-width-at-half-maximum timing resolution is measured with an avalanche photo diode and a laser setup. The power consumption is 2.5 mW using 0.5 and 1.2 V power supplies. The proposed ASIC is implemented in a 90 nm TSMC CMOS process with a total area of 3.3 mm \times 2.7 mm.
Auteurs: Hugo Cruz;Hong-Yi Huang;Ching-Hsing Luo;Shuenn-Yuh Lee;
Apparue dans: IEEE Transactions on Biomedical Circuits and Systems
Date publication: 04.-2017, volume: 11, issue:2, pages: 287 - 299
Editeur: IEEE
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» A 20-pW Discontinuous Switched-Capacitor Energy Harvester for Smart Sensor Applications
Résumé:
We present a discontinuous harvesting approach for switch capacitor dc–dc converters that enables ultralow-power energy harvesting. Smart sensor applications rely on ultralow-power energy harvesters to scavenge energy across a wide range of ambient power levels and charge the battery. Based on the key observation that energy source efficiency is higher than charge pump efficiency, we present a discontinuous harvesting technique that decouples the two efficiencies for a better tradeoff. By slowly accumulating charge on an input capacitor and then transferring it to a battery in burst mode, dc–dc converter switching and leakage losses can be optimally traded off with the loss incurred by nonideal maximum power point tracking operation. Harvester duty cycle is automatically modulated instead of charge pump operating frequency to match with the energy source input power level. The harvester uses a hybrid structure called a moving-sum charge pump for low startup energy upon a mode switch, an automatic conversion ratio modulator based on conduction loss optimization for fast conversion ratio increment, and a <15-pW asynchronous mode controller for ultralow-power operation. In 180-nm CMOS, the harvester achieves >40% end-to-end efficiency from 113 pW to 1.5 $mu text{W}$ with 20-pW minimum harvestable input power.
Auteurs: Xiao Wu;Yao Shi;Supreet Jeloka;Kaiyuan Yang;Inhee Lee;Yoonmyung Lee;Dennis Sylvester;David Blaauw;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 972 - 984
Editeur: IEEE
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» A 200–1380-kHz Quadrifrequency Focused Ultrasound Transducer for Neurostimulation in Rodents and Primates: Transcranial In Vitro Calibration and Numerical Study of the Influence of Skull Cavity
Résumé:
Low intensity transcranial focused ultrasound has been demonstrated to produce neuromodulation in both animals and humans. Primarily for technical reasons, frequency is one of the most poorly investigated critical wave parameters. We propose the use of a quadri-band transducer capable of operating at 200, 320, 850, and 1380 kHz for further investigation of the frequency dependence of neuromodulation efficacy while keeping the position of the transducer fixed with respect to the subject’s head. This paper presents the results of the transducer calibration in water, in vitro transmission measurements through a monkey skull flap, 3-D simulations based on both a $mu $ -computed tomography ( $mu $ CT)-scan of a rat and on CT-scans of two macaques. A maximum peak pressure greater than 0.52 MPa is expected at each frequency in rat and macaque heads. According to the literature, our transducer can achieve neuromodulation in rodents and primates at each four frequencies. The impact of standing waves is shown to be most prominent at the lowest frequencies.
Auteurs: Charlotte Constans;Thomas Deffieux;Pierre Pouget;Mickaël Tanter;Jean-François Aubry;
Apparue dans: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Date publication: 04.-2017, volume: 64, issue:4, pages: 717 - 724
Editeur: IEEE
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» A 220/247.5/275-GHz, 1.0-MW, Triple Frequency Regime Gyrotron
Résumé:
In this paper, a complete design methodology of a triple frequency gyrotron is presented, which can also be further applied to multifrequency operations. Frequencies for operation are selected as 220, 247.5, and 275 GHz for the localized and intense heating of magnetically confined plasmas (i.e., electron cyclotron heating and current drive) for future fusion reactors. A cautious selection procedure of the mode triplet is portrayed in accordance with the all possible physical and technical constraints. Typical cold cavity (beam absent) and single-mode (beam present) calculations are performed and presented with extended interaction structure (including an optimized nonlinear taper section). A triode type configuration is adopted for magnetron injection gun to produce the electron beam with desired characteristics as required for RF behavior. Time-dependent multimode calculations are presented with nonuniform magnetic field and beam parameters optimized by gun simulations. These rigorous calculations affirm proper working of the design with \approx 1 -MW continuous wave power for chosen mode triplet and efficiency \approx 35 %.
Auteurs: Gaurav Singh Baghel;M. V. Kartikeyan;Manfred K. Thumm;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 04.-2017, volume: 64, issue:4, pages: 1774 - 1780
Editeur: IEEE
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» A 23-mW 24-GS/s 6-bit Voltage-Time Hybrid Time-Interleaved ADC in 28-nm CMOS
Résumé:
This paper presents a power- and area-efficient 16-way time-interleaved (TI) analog-to-digital converter (ADC) achieving 24-GS/s conversion speed and 6-bit resolution in 28-nm CMOS. A voltage-time hybrid pipeline technique exploiting the comparator input-voltage-output-time dependency is reported to enhance the throughput of successive-approximation-register (SAR) ADCs. A reference-buffer-free capacitive digital-to-analog (CDAC) converter is utilized to mitigate the crosstalk problem in TI-ADCs. Timing mismatches between individual sub-ADCs are estimated with a reference-ADC dithering technique and corrected by digitally controlled delay lines (DCDL). The techniques collectively enabled a very compact design, obviating any input buffer or hierarchical sampling structures. The ADC core consumes 23 mW and occupies an area of 0.03 mm2. A signal-to-noise plus distortion ratio (SNDR) of 35 dB and a spurious-free dynamic range (SFDR) of 54 dB were measured for a 40-MHz input. For a Nyquist input, the prototype measured an SNDR of 29 dB and an SFDR of 41 dB with all timing mismatch spurs suppressed below −50 dBc after skew calibration.
Auteurs: Benwei Xu;Yuan Zhou;Yun Chiu;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1091 - 1100
Editeur: IEEE
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» A 3-D Split-Step Fourier Algorithm Based on a Discrete Spectral Representation of the Propagation Equation
Résumé:
A propagation method self-consistent in the discrete domain for the simulation of large distance scenarios in a 3-D inhomogeneous atmosphere is proposed. First, a spectral representation of the field in a discrete 3-D domain over an infinite perfect ground is introduced in cylindrical coordinates. A discrete spectral propagator is then derived. As in 2-D methods, the inhomogeneous atmosphere is considered in the spatial domain using phase screens. An explicit numerical scheme is introduced. For directive sources, a sectoral propagation is proposed to reduce the computation time by limiting the computation domain. The method is tested by simulation scenarios involving refractive effects in both vertical and azimuthal directions. The 3-D refractive effects are shown to be properly simulated.
Auteurs: Hang Zhou;Alexandre Chabory;Rémi Douvenot;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1988 - 1995
Editeur: IEEE
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» A 4-fJ/b Delay-Hardened Physically Unclonable Function Circuit With Selective Bit Destabilization in 14-nm Trigate CMOS
Résumé:
This paper describes a full-entropy 128-b key generation platform based on a 1024-b hybrid physically unclonable function (PUF) array, fabricated in 14-nm trigate high-k/metal-gate CMOS. Delay-hardened hybrid PUF cells use differential clock delay insertion to favor circuit evaluation in the desired direction while leveraging burn-in-induced aging for selective bit destabilization enabling quick identification and masking of unstable cells, and subsequent temporal-majority-voting with soft dark-bit masking to reduce PUF bit error by 3.9 times to 1.45% resulting in ~5 ppb failure probability. A stable full-entropy 128-b key is finally generated from the 1024 raw PUF bits using BCH error correction and AES-CBC-based entropy extraction. An all-digital design with compact PUF cell layout occupying $1.84~mu text{m}^{2}$ achieves: 1) 4-fJ/b energy-efficiency with 3-μW leakage at 0.65 V, 70 °C; 2) peak operating frequency of 1 GHz resulting in 1.2-μs key generation latency; 3) robust operation with stable key generation across 0.55–0.75 V, and 25 °C–110 °C; 4) 14 times separation between intra/inter-PUF hamming distances with 0.99993 entropy ensuring cryptographic quality randomness and uniqueness; 5) 48% higher PUF stability with long-term aging by leveraging transistor degradation to reinforce favorable cell bias; and 6) resiliency to power cycling attacks with common centroid clock routing measured from 49.5% hamming distance between array’s evaluation and wake-up states.
Auteurs: Sudhir Satpathy;Sanu K. Mathew;Vikram Suresh;Mark A. Anders;Himanshu Kaul;Amit Agarwal;Steven K. Hsu;Gregory Chen;Ram K. Krishnamurthy;Vivek K. De;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 940 - 949
Editeur: IEEE
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» A 4-W Doherty Power Amplifier in GaN MMIC Technology for 15-GHz Applications
Résumé:
This letter presents an integrated Doherty power amplifier (PA) in 0.25- $mu text{m}$ GaN on SiC process. Designed for 15-GHz point-to-point radios, the PA exhibits an output power of 36 ± 0.5 dBm between 13.7 and 15.3 GHz, while at 14.6 GHz, it shows a 6-dB output back-off efficiency higher than 28%. Modulated signal measurements applying digital predistortion demonstrate the compatibility of the amplifier with point-to-point radio requirements. To the best of our knowledge, this PA has the highest back-off efficiency for the 15-GHz band, and is the first GaN Doherty in the Ku-band.
Auteurs: Roberto Quaglia;Vittorio Camarchia;Jorge Julian Moreno Rubio;Marco Pirola;Giovanni Ghione;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 365 - 367
Editeur: IEEE
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» A 5 Gb/s Voltage-Mode Transmitter Using Adaptive Time-Based De-Emphasis
Résumé:
A 5-Gb/s voltage-mode (VM) transmitter using adaptive time-based de-emphasis is presented. The duty cycle of the pulse-width modulation data is adjusted by the spectrum-balancing technique. This adaptive VM transmitter does not need an auxiliary cable. It can adaptively compensate the loss of the channels with different lengths. This transmitter and a receiver are fabricated in a 40-nm CMOS process. The active areas of the transmitter and the receiver are 0.075 mm2 and 0.105 mm2, respectively. For a 1.1 V supply voltage, the power of the transmitter is 9.3 mW and the total power of the transceiver is 17.5 mW. For a 5-Gb/s PRBS of 27-1 passing through a 9-m coaxial cable with a 15.35-dB loss, the measured root-mean-square and peak-to-peak jitters of the recovered data are 12.25 and 64.44 ps, respectively. The settling time for adaptive time-based de-emphasis is 2.048 $mu text{s}$ . The measured bit error rate is less than 10−12.
Auteurs: Wun-Jian Su;Shen-Iuan Liu;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 959 - 968
Editeur: IEEE
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» A 56-Gb/s PAM4 Wireline Transceiver Using a 32-Way Time-Interleaved SAR ADC in 16-nm FinFET
Résumé:
A 56-Gb/s PAM4 wireline transceiver testchip is implemented in 16-nm FinFET. The current mode logic transmitter incorporates an auxiliary current injection at the output nodes to maintain PAM4 amplitude linearity. The ADC-based receiver incorporates hybrid analog and digital equalizations. The analog equalization is performed using two identical stages of continuous time linear equalizer, each having a constant of ~0-dB dc-gain and a maximum peaking of ~7 dB peaking at 14 GHz. A 28-GSample/s 32-way time-interleaved SAR ADC converts the equalized analog signal into digital domain for further equalization using digital signal processing. The transceiver achieves <1e-8 bit error rate over a backplane channel with 31-dB loss at 14-GHz and 3.5-mVrms additional crosstalk, using a fixed ~10-dB TX equalization and an adaptive hybrid RX equalization, with the DSP configured to have a 24-tap feed forward equalizer and a 1-tap decision feedback equalizer. The transceiver consumes 550-mW power at 56 Gb/s, excluding the power of the on-chip configurable DSP that cannot be accurately measured as it is implemented as part of a larger test structure.
Auteurs: Yohan Frans;Jaewook Shin;Lei Zhou;Parag Upadhyaya;Jay Im;Vassili Kireev;Mohamed Elzeftawi;Hiva Hedayati;Toan Pham;Santiago Asuncion;Chris Borrelli;Geoff Zhang;Hongtao Zhang;Ken Chang;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1101 - 1110
Editeur: IEEE
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» A 60-GHz CMOS Transceiver With On-Chip Antenna and Periodic Near Field Directors for Multi-Gb/s Contactless Connector
Résumé:
A 60-GHz-based millimeter-wave (mm-wave)-wireless-interconnect (M2W2-I) with noncoherent amplitude shift-key (ASK) modulation is presented for applications in multigigabit ultrashort distance contactless connector. M2W2-I modulates data at mm-wave frequencies and transmits over the air in a very short distance (5 mm or less). A folded-dipole antenna is designed on-chip for a compact package form-factor, and a periodic near field director (PNFD) is inserted between transmitter (TX) and receiver (RX) to enhance a communication distance. Designed and fabricated in 65-nm CMOS, the M2W2-I achieves 5 Gb/s with 0.5 mm separation of air-coupling and 5.7-Gb/s 5-mm separation through a PNFD inserted channel. The measured energy efficiency is 7 pJ/bit using a PNFD.
Auteurs: Yanghyo Kim;Sai-Wang Tam;Tatsuo Itoh;Mau-Chung Frank Chang;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 404 - 406
Editeur: IEEE
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» A 65-nm CMOS Constant Current Source With Reduced PVT Variation
Résumé:
This paper presents a new nanometer-based low-power constant current reference that attains a small value in the total process–voltage–temperature variation. The circuit architecture is based on the embodiment of a process-tolerant bias current circuit and a scaled process-tracking bias voltage source for the dedicated temperature-compensated voltage-to-current conversion in a preregulator loop. Fabricated in a UMC 65-nm CMOS process, it consumes 7.18~\mu text{W} with a 1.4 V supply. The measured results indicate that the current reference achieves an average temperature coefficient of 119 ppm/°C over 12 samples in a temperature range from −30 °C to 90 °C without any calibration. Besides, a low line sensitivity of 180 ppm/V is obtained. This paper offers a better sensitivity figure of merit with respect to the reported representative counterparts.
Auteurs: Dong Wang;Xiao Liang Tan;Pak Kwong Chan;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1373 - 1385
Editeur: IEEE
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» A 73.9%-Efficiency CMOS Rectifier Using a Lower DC Feeding (LDCF) Self-Body-Biasing Technique for Far-Field RF Energy-Harvesting Systems
Résumé:
A self-body-biasing technique is proposed for differential-drive cross-coupled (DDCC) rectifier, with its profound application in far-field RF energy-harvesting systems. The conventional source-to-body, and the proposed technique known as Lower DC Feeding (LDCF), were fabricated in the 130-nm CMOS and compared at the operation frequency of 500 MHz, 953 MHz and 2 GHz along with a corresponding load of $2~text {k}Omega $ , $10~text {k}Omega $ and $50~text {k}Omega $ . The technique allows the PMOS transistors to operate with a dynamic threshold voltage ( $V_{th}$ ) which improves the power conversion efficiency (PCE) when the rectifier is operating at a smaller received power. A 9.5% of improvement is achieved at the peak PCE when the rectifier is operating at 953 MHz, and driving a $10~text {k}Omega $ load. A maximum PCE of 73.9% is measured at 2 GHz when driving a 2- $text {k}Omega $ load. The LDCF technique also offers a self-limiting capability for its output voltage, by reducing the PCE at larger received power. A limit-voltage level of 3.5 V is measured irrespective to the operating frequency and load. This capability aids the protection of the subsequent circuits in a wireless sensor from being overpowered.
Auteurs: Amin Khalili Moghaddam;Joon Huang Chuah;Harikrishnan Ramiah;Jalil Ahmadian;Pui-In Mak;Rui P. Martins;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 992 - 1002
Editeur: IEEE
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» A Bayesian-Network-Based Classification Method Integrating Airborne LiDAR Data With Optical Images
Résumé:
Point cloud classification is of great importance to applications of airborne Light Detection And Ranging (LiDAR) data. In recent years, airborne LiDAR has been integrated with various other sensors, e.g., optical imaging sensors, and thus, the fusion of multiple data types for scene classification has become a hot topic. Therefore, this paper proposes a Bayesian network (BN) model that is suitable for airborne point cloud classification fusing multiple data types. Based on an analysis of the characteristics of LiDAR point clouds and aerial images, we first extract the geometric features from the point clouds and the spectral features from the optical images. The optimal BN structure is then trained using an improved mutual-information-based K2 algorithm to obtain the optimal BN classifier for point cloud classification. Experiments demonstrate that the BN classifier can effectively distinguish four types of basic ground objects, including ground, vegetation, trees, and buildings, with a high accuracy of over 90%. Moreover, compared with other classifiers, the proposed BN classifier can achieve the highest overall accuracies, and in particular, the classifier demonstrates its advantage in the classification of ground and low vegetation points.
Auteurs: Zhizhong Kang;Juntao Yang;Ruofei Zhong;
Apparue dans: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date publication: 04.-2017, volume: 10, issue:4, pages: 1651 - 1661
Editeur: IEEE
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» A Bilevel Approach for the Stochastic Optimal Operation of Interconnected Microgrids
Résumé:
Smart grid planning and control is becoming a theme of high interest in the last years. This is due to the presence of distributed generation, power from renewable resources and storage systems, to the different actors present over the territory, and to the difficulty of defining appropriate models for decision support. A bilevel optimal control scheme is proposed for grids characterized by renewable and traditional power production, bidirectional power flows, dynamic storage systems, and stochastic modeling issues. In this scheme, the upper level decision maker (UDM) views the lower level decision makers (LDMs) or microgrids as single nodes. In the statement of the UDM problem, the LDM control strategies are structurally and parametrically constrained inside a nonlinear optimization problem that includes load flow equations. Then, the LDMs can follow references from the UDM and use available information at the local level to solve a stochastic optimization problem. The proposed control architecture has been applied to a specific case study (Savona, Italy).
Auteurs: Riccardo Minciardi;Michela Robba;
Apparue dans: IEEE Transactions on Automation Science and Engineering
Date publication: 04.-2017, volume: 14, issue:2, pages: 482 - 493
Editeur: IEEE
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» A BJT-Based Temperature-to-Digital Converter With ±60 mK ( $3~sigma$ ) Inaccuracy From −55 °C to +125 °C in 0.16-μm CMOS
Résumé:
This paper presents a precision CMOS temperature-to-digital converter (TDC), which senses the temperature-dependent base–emitter voltage of substrate PNPs. Measurements on 20 samples from one batch show that it achieves an inaccuracy of ±60 mK ( $3~sigma $ ) from −55 °C to +125 °C, after a single room-temperature trim. This state-of-the-art result is mainly due to the extensive use of dynamic error cancellation techniques to generate the PNP’s collector currents, thus minimizing the spread in their base–emitter voltages, together with a digital PTAT trim to correct for the spread in the PNP’s saturation currents. The effect of process variation on the TDC’s inaccuracy was investigated by measuring 80 samples from three different batches. Using the same calibration parameters, they exhibit a maximum untrimmed inaccuracy of ±2 °C ( $3~sigma $ ) from −55 °C to +125 °C. This drops to ±100 mK ( $3~sigma $ ) after a single point trim. The proposed TDC thus reduces calibration costs by obviating the need for batch-specific calibration parameters, which would otherwise require the multipoint calibration of several samples. The effect of the PNP’s current gain $beta $ was also investigated with the help of a novel $beta $ -detection circuit. Implemented in 0.16-μm- CMOS, the TDC occupies 0.16 mm2 and draws 4.6 $mu text{A}$ from 1.5 to 2 V supply voltages. It achieves a resolution Figure of Merit of 7.8 pJ°C2, and a state-of-the-art supply sensitivity of 0.01 °C/V.
Auteurs: Bahman Yousefzadeh;Saleh Heidary Shalmany;Kofi A. A. Makinwa;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1044 - 1052
Editeur: IEEE
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» A Bluetooth Low-Energy Transceiver With 3.7-mW All-Digital Transmitter, 2.75-mW High-IF Discrete-Time Receiver, and TX/RX Switchable On-Chip Matching Network
Résumé:
We present an ultra-low-power Bluetooth low-energy (BLE) transceiver (TRX) for the Internet of Things (IoT) optimized for digital 28-nm CMOS. A transmitter (TX) employs an all-digital phase-locked loop (ADPLL) with a switched current-source digitally controlled oscillator (DCO) featuring low frequency pushing, and class-E/F2 digital power amplifier (PA), featuring high efficiency. Low 1/ $f$ DCO noise allows the ADPLL to shut down after acquiring lock. The receiver operates in discrete time at high sampling rate (~10 Gsamples/s) with intermediate frequency placed beyond 1/ $f$ noise corner of MOS devices. New multistage multirate charge-sharing bandpass filters are adapted to achieve high out-of-band linearity, low noise, and low power consumption. An integrated on-chip matching network serves to both PA and low-noise transconductance amplifier, thus allowing a 1-pin direct antenna connection with no external band-selection filters. The TRX consumes 2.75 mW on the RX side and 3.7 mW on the TX side when delivering 0 dBm in BLE.
Auteurs: Feng-Wei Kuo;Sandro Binsfeld Ferreira;Huan-Neng Ron Chen;Lan-Chou Cho;Chewn-Pu Jou;Fu-Lung Hsueh;Iman Madadi;Massoud Tohidian;Mina Shahmohammadi;Masoud Babaie;Robert Bogdan Staszewski;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 1144 - 1162
Editeur: IEEE
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» A Broadband Passive Monopulse Comparator MMIC
Résumé:
A broadband monopulse comparator MMIC (Monolithic Microwave Integrated Circuit) based on GaAs process is presented in this Letter. The comparator network constructed by three magic tees and one lumped power divider is proposed for one sum channel and two delta channels. The measurement results show that very wide frequency band from 15 to 30 GHz (66.7% relatively frequency bandwidth) with less than 2.5-dB loss can be achieved for the sum channel. And the null depth is more than 22 dB in 15–27GHz and 17 dB in 27–30 GHz for two delta channels. The total chip size is 3.4 mm 3.4 mm ( $0.26lambda _{0}~0.26lambda _{0}$ at the center frequency of 22.5 GHz).
Auteurs: Yang Chen;Yuehang Xu;Liulin Hu;Wei Tong;Ruimin Xu;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 359 - 361
Editeur: IEEE
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» A Broadband Printed Monofilar Square Spiral Antenna : A circularly polarized low-profile antenna.
Résumé:
This article presents a novel circularly polarized (CP) wide-band printed monofilar square spiral antenna (MSSA) with a low profile and 50-X input impedance, as well as a technique to improve the overlapped bandwidth and reduce the profile of a conventional MSSA. To extend the application of the present design to an array antenna, a square cavity is introduced. This simple and low-cost approach results in a wide-band printed MSSA with high directivity. To verify this design concept, antenna prototypes operating at Ku frequency band have been designed and fabricated. Simulation and measurement results show that the present designs have more than 16% 10-dB return loss and 3-dB axial ratio (AR) bandwidth within the same frequency range with high radiation efficiency. The beam-scanning performance of the array antenna using the present design was investigated, and the calculated results suggest that good CP performance is obtained during the beam scanning. The advantages of our MSSA design are wide overlapped bandwidth, low profile, flexibility in antenna performance tuning, and easy fabrication. The present antennas have the potential to be used in small satellites such as microsatellites and CubeSats for tracking, command function, and data downlink applications.
Auteurs: Qi Luo;Steven Gao;Mohammed Sobhy;Jianzhou Li;Gao Wei;Jiadong Xu;
Apparue dans: IEEE Antennas and Propagation Magazine
Date publication: 04.-2017, volume: 59, issue:2, pages: 79 - 87
Editeur: IEEE
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» A Characterization of Minimum Spanning Tree-Like Metric Spaces
Résumé:
Recent years have witnessed a surge of biological interest in the minimum spanning tree (MST) problem for its relevance to automatic model construction using the distances between data points. Despite the increasing use of MST algorithms for this purpose, the goodness-of-fit of an MST to the data is often elusive because no quantitative criteria have been developed to measure it. Motivated by this, we provide a necessary and sufficient condition to ensure that a metric space on $n$ points can be represented by a fully labeled tree on $n$ vertices, and thereby determine when an MST preserves all pairwise distances between points in a finite metric space.
Auteurs: Momoko Hayamizu;Hiroshi Endo;Kenji Fukumizu;
Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Date publication: 04.-2017, volume: 14, issue:2, pages: 468 - 471
Editeur: IEEE
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» A Characterization of Switched Linear Control Systems With Finite $L_{2}$-Gain
Résumé:
Motivated by an open problem posed by J. P. Hespanha, we extend the notion of Barabanov norm and extremal trajectory to classes of switching signals that are not closed under concatenation. We use these tools to prove that the finiteness of the $L_{2}$-gain is equivalent, for a large set of switched linear control systems, to the condition that the generalized spectral radius associated with any minimal realization of the original switched system is smaller than one.
Auteurs: Yacine Chitour;Paolo Mason;Mario Sigalotti;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 04.-2017, volume: 62, issue:4, pages: 1825 - 1837
Editeur: IEEE
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» A Chopper Instrumentation Amplifier With Input Resistance Boosting by Means of Synchronous Dynamic Element Matching
Résumé:
In this work, we propose a method to increase the parasitic input resistance caused by application of chopper modulation to indirect current feedback instrumentation amplifiers. The result is obtained by applying dynamic element matching to the input and feedback ports at the same frequency as chopper modulation. The proposed approach requires effective offset ripple rejection and equalization of the input and feedback common mode voltages. An in-amp architecture that meets both requirements and embodies the proposed input resistance boosting method is described. Experimental verification is provided by means of a prototype designed and fabricated using the $0.32~mu text {m}$ CMOS devices of the STMicroelectronics BCD6s process. The amplifier operates with a 3.3 V supply voltage and a total current absorption of $170~mu text {A}$ . An input impedance in excess of $1~text {G}Omega $ has been measured at a chopper frequency of 20 kHz. The input referred voltage noise density is 18 nV/sqrt(Hz) with a flicker corner of 0.2 Hz and 200 Hz bandwidth.
Auteurs: Federico Butti;Massimo Piotto;Paolo Bruschi;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 753 - 764
Editeur: IEEE
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» A Class of Weiss–Weinstein Bounds and Its Relationship With the Bobrovsky–Mayer-Wolf–Zakaï Bounds
Résumé:
A fairly general class of Bayesian “large-error” lower bounds of the Weiss–Weinstein family, essentially free from regularity conditions on the probability density functions support, and for which a limiting form yields a generalized Bayesian Cramér–Rao bound (BCRB), is introduced. In a large number of cases, the generalized BCRB appears to be the Bobrovsky–Mayer-Wolf–Zakai bound (BMZB). Interestingly enough, a regularized form of the Bobrovsky–Zakai bound (BZB), applicable when the support of the prior is a constrained parameter set, is obtained. Modified Weiss–Weinstein bound and BZB which limiting form is the BMZB are proposed, in expectation of an increased tightness in the threshold region. Some of the proposed results are exemplified with a reference problem in signal processing: the Gaussian observation model with parameterized mean and uniform prior.
Auteurs: Eric Chaumette;Alexandre Renaux;Mohammed Nabil El Korso;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 04.-2017, volume: 63, issue:4, pages: 2226 - 2240
Editeur: IEEE
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» A Classroom Scheduling Service for Smart Classes
Résumé:
During past decades, the classroom scheduling problem has posed significant challenges to educational programmers and teaching secretaries. In order to alleviate the burden of the programmers, this paper presents SmartClass, which allows the programmers to solve this problem using web services. By introducing service-oriented architecture (SOA), SmartClass is able to provide classroom scheduling services with back-stage design space exploration and greedy algorithms. Furthermore, the SmartClass architecture can be dynamically coupled to different scheduling algorithms (e.g. Greedy, DSE, etc.) to fit in specific demands. A typical case study demonstrates that SmartClass provides a new efficient paradigm to the traditional classroom scheduling problem, which could achieve high flexibility by software services reuse and ease the burden of educational programmers. Evaluation results on efficiency, overheads and scheduling performance demonstrate the SmartClass has lower scheduling overheads with higher efficiency.
Auteurs: Chao Wang;Xi Li;Aili Wang;Xuehai Zhou;
Apparue dans: IEEE Transactions on Services Computing
Date publication: 04.-2017, volume: 10, issue:2, pages: 155 - 164
Editeur: IEEE
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» A Closed-Loop Fuzzy-Logic-Based Current Controller for PMSM Torque Ripple Minimization Using the Magnitude of Speed Harmonic as the Feedback Control Signal
Résumé:
This paper investigates torque ripple minimization for permanent-magnet synchronous machine (PMSM), and proposes a closed-loop fuzzy-logic-based current controller by using the magnitude of the speed harmonic as the feedback control signal. The speed harmonic can be obtained from machine speed measurement, so the proposed approach does not require accurate machine parameters and is not influenced by the nonlinearity of the machine and drive. The torque harmonic can produce the speed harmonic of the same order, so their relation is investigated, which shows that the magnitude of the speed harmonic is proportional to the magnitude of the torque harmonic of the same order, so it can be used as a measure of torque harmonic for torque ripple minimization. Then, the torque harmonic model is developed to facilitate the design and analysis of the current controller. Afterward, a novel fuzzy-logic-based current controller is proposed to minimize the dominant torque harmonics. The proposed current controller is evaluated on a laboratory PMSM drive system under different load conditions and operation speeds.
Auteurs: Guodong Feng;Chunyan Lai;Narayan C. Kar;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 2642 - 2653
Editeur: IEEE
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» A CMOS 3–12-GHz Ultrawideband Low Noise Amplifier by Dual-Resonance Network
Résumé:
A low-power and high power-gain ( $S_{21}$ ) ultrawideband low noise amplifier (UWB LNA) with flat noise figure (NF) based on Global Foundies 0.13- $mu text{m}$ CMOS technology is reported. The load effect of common-gate (CG) topology is applied with dual-resonance load network for both wideband input matching and NF flatness. Combined with inductive-series peaking technique, the frequency response of CG-common-source cascade topology is further extended. The LNA circuit achieves the high and flat power gain of 13.5 ± 1.5 dB with input return loss better than 13 dB and a flat NF of 4.3 dB ±0.4 dB for frequencies 3–12 GHz. The fabricated LNA occupies a die area of 1.09 0.8 mm2 including pads and draw 8.5 mW from 1.2-V dc supply.
Auteurs: Nan Li;Weiwei Feng;Xiuping Li;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 383 - 385
Editeur: IEEE
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» A CMOS Current Steering Neurostimulation Array With Integrated DAC Calibration and Charge Balancing
Résumé:
An 8-channel current steerable, multi-phasic neural stimulator with on-chip current DAC calibration and residue nulling for precise charge balancing is presented. Each channel consists of two sub-binary radix DACs followed by wide-swing, high output impedance current buffers providing time-multiplexed source and sink outputs for anodic and cathodic stimulation. A single integrator is shared among channels and serves to calibrate DAC coefficients and to closely match the anodic and cathodic stimulation phases. Following calibration, the differential non-linearity is within  \pm 0.3 LSB at 8-bit resolution, and the two stimulation phases are matched within 0.3%. Individual control in digital programming of stimulation coefficients across the array allows altering the spatial profile of current stimulation for selection of stimulation targets by current steering. Combined with the self-calibration and current matching functions, the current steering capabilities integrated on-chip support use in fully implanted neural interfaces with autonomous operation for and adaptive stimulation under variations in electrode and tissue conditions. As a proof-of-concept we applied current steering stimulation through a multi-channel cuff electrode on the sciatic nerve of a rat.
Auteurs: Elliot Greenwald;Christoph Maier;Qihong Wang;Robert Beaulieu;Ralph Etienne-Cummings;Gert Cauwenberghs;Nitish Thakor;
Apparue dans: IEEE Transactions on Biomedical Circuits and Systems
Date publication: 04.-2017, volume: 11, issue:2, pages: 324 - 335
Editeur: IEEE
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» A Compact Dual-Band Beam-Sweeping Antenna Based on Active Frequency Selective Surfaces
Résumé:
A dual-band beam-sweeping antenna based on two independent cylindrical active frequency selective surfaces (AFSSs) is proposed in this paper. This antenna is composed of a dual-band omnidirectional monopole antenna operating at 2.45 and 5.2 GHz and two cylindrical AFSS screens. The dual-band omnidirectional monopole antenna is designed as a radiating source and surrounded by the proposed two cylindrical AFSS screens. The unit cells of the two proposed AFSS screens consist of two metallic crosses connected by a pin diode vertically. By switching the pin diodes, the transmission and reflection characteristics of unit cell of the two AFSS are investigated, respectively, at their own operating frequency. This leads to the variation of the radiation pattern when the cylindrical AFSS screens are loaded around the monopole antenna. Therefore, by switching the pin diodes with specified combinations, the dual-band beamforming antenna with multiple discrete states can be achieved at 2.45 and 5.2 GHz.
Auteurs: Jinxin Li;Qingsheng Zeng;Ruizhi Liu;Tayeb A. Denidni;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1542 - 1549
Editeur: IEEE
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» A Comparative Study 4500-V Edge Termination Techniques for SiC Devices
Résumé:
This paper compares five edge termination techniques for SiC high-voltage devices: single zone junction termination extension (JTE), ring assisted-JTE (RA-JTE), multiple floating zone-JTE, hybrid-JTE, and floating field rings. PiN diodes with these edge terminations were fabricated on a 4.5kV-rated 4H-silicon carbide (4H-SiC) epi-layer. It was experimentally demonstrated that the Hybrid-JTE provides a nearly ideal breakdown voltage (~ 99% of the ideal parallel plane breakdown voltage) with a stable avalanche blocking behavior. RA-JTE, with tight control of the JTE implant dose, is demonstrated to be the most area-efficient edge termination structure for SiC power devices.
Auteurs: Woongje Sung;B. Jayant Baliga;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 04.-2017, volume: 64, issue:4, pages: 1647 - 1652
Editeur: IEEE
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» A Comparison of Bidding Strategies for Online Auctions Using Fuzzy Reasoning and Negotiation Decision Functions
Résumé:
Bidders often feel challenged when looking for the best bidding strategies to excel in the competitive environment of multiple and simultaneous online auctions for same or similar items. Bidders face complicated issues for deciding which auction to participate in, whether to bid early or late, and how much to bid. In this paper, we present the design of bidding strategies, which aim to forecast the bid amounts for buyers at a particular moment in time based on their bidding behavior and their valuation of an auctioned item. The agent develops a comprehensive methodology for final price estimation, which designs bidding strategies to address buyers’ different bidding behaviors using two approaches: Mamdani method with regression analysis and negotiation decision functions. The experimental results show that the agents who follow fuzzy reasoning with a regression approach outperform other existing agents in most settings in terms of their success rate and expected utility.
Auteurs: Preetinder Kaur;Madhu Goyal;Jie Lu;
Apparue dans: IEEE Transactions on Fuzzy Systems
Date publication: 04.-2017, volume: 25, issue:2, pages: 425 - 438
Editeur: IEEE
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» A Comprehensive DC and AC PBTI Modeling Framework for HKMG n-MOSFETs
Résumé:
A physics-based modeling framework is proposed to calculate the threshold voltage shift ( \Delta text{V}_{math\rm {T}}) in planar high-k metal gate (HKMG) n-MOSFETs for positive bias temperature instability (PBTI). Overall \Delta text{V}_{math\rm { {T}}} is estimated using the uncorrelated contributions from the trap generation (TG) and the electron trapping subcomponents. The time evolution of \Delta text{V}_{math\rm { {T}}} , measured using an ultrafast measure-stress-measure method during dc and ac stress and after dc stress, is predicted for different experimental conditions. The modeled TG component is verified by independent direct-current I–V method. The proposed model explains PBTI in differently processed HKMG gate stacks.
Auteurs: Subhadeep Mukhopadhyay;Narendra Parihar;Nilesh Goel;Souvik Mahapatra;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 04.-2017, volume: 64, issue:4, pages: 1474 - 1481
Editeur: IEEE
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» A Comprehensive Design Approach of Power Electronic-Based Distributed Generation Units Focused on Power-Quality Improvement
Résumé:
The undesirable harmonic distortion produced by distributed generation units (DGUs) based on power-electronic inverters presents operating and power-quality challenges in electric systems. The level of distortion depends on the internal elements of the DGUs as well as on the characteristics of the grid, loads, and controls, among others. This paper presents a comprehensive method, focused on power-quality indexes and efficiency for the design of microgrids with multiple DGUs interconnected to the ac grid through three-phase multi-Megawatt medium-voltage pulsewidth-modulated-voltage-source inverters (PWM-VSI). The proposed design method is based on a least square solution using the harmonic domain modeling approach to effectively consider explicitly the harmonic characteristics of the DGUs and their direct and cross-coupling interaction with the grid, loads, and the other DGUs. Extensive simulations and analyses against PSCAD are presented in order to show the outstanding performance of the proposed design approach.
Auteurs: Miguel Esparza;Juan Segundo;C. Núñez;Xiongfei Wang;Frede Blaabjerg;
Apparue dans: IEEE Transactions on Power Delivery
Date publication: 04.-2017, volume: 32, issue:2, pages: 942 - 950
Editeur: IEEE
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» A Compressed Sensing Strategy for Synthetic Transmit Aperture Ultrasound Imaging
Résumé:
A novel beamforming technique, named compressed sensing based synthetic transmit aperture (CS-STA) is proposed to speed up the acquisition of ultrasound imaging. This technique consists of three steps. First, the ultrasound transducer transmits randomly apodized plane waves for a number of times and receives the backscattered echoes. Second, the recorded backscattered echoes are used to recover the full channel dataset of synthetic transmit aperture (STA) with a compressed sensing (CS) reconstruction algorithm. Finally, an STA image is beamformed from the recovered full STA dataset. As CS allows recovering a signal from its few linear measurements with high probability, CS-STA is capable of recovering the STA image with fewer firings (i.e., higher frame rate) and retaining the high resolution of STA. In addition, the contrast of the STA image can be improved at the same time owing to the higher energy of plane wave firing in CS-STA. Simulations demonstrate that CS-STA is capable of recovering the STA channel dataset with a smaller number of firings. The performance of CS-STA is evaluated in phantom experiments through comparisons with STA, multi-element STA, conventional focused mode and coherent plane wave imaging. The results demonstrate that, implemented with the same frame rate, CS-STA achieves higher or comparable resolution and contrast. Moreover, comparisons are conducted on the biceps brachii muscle and thyroid of a human subject, and the results demonstrate the feasibility and competitiveness of CS-STA in the in vivo conditions.
Auteurs: Jing Liu;Qiong He;Jianwen Luo;
Apparue dans: IEEE Transactions on Medical Imaging
Date publication: 04.-2017, volume: 36, issue:4, pages: 878 - 891
Editeur: IEEE
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» A Compressibility-Based Clustering Algorithm for Hierarchical Compressive Data Gathering
Résumé:
Data gathering in wireless sensor networks (WSNs) is one of the major sources for power consumption. Compression is often employed to reduce the number of packet transmissions required for data gathering. However, conventional data compression techniques can introduce heavy in-node computation, and thus, the use of compressive sensing (CS) for WSN data gathering has recently attracted growing attention. Among existing CS-based data gathering approaches, hierarchical compressive data gathering (HCDG) methods currently offer the most transmission-efficient architectures. When employing HCDG, clustering algorithms can affect the number of data transmissions. Most existing HCDG works use the random clustering (RC) method as a clustering algorithm, which can produce significant number of transmissions in some cases. In this paper, we present a compressibility-based clustering algorithm (CBCA) for HCDG. In CBCA, the network topology is first converted into a logical chain, similar to the idea proposed in PEGASIS [1], and then the spatial correlation of the cluster nodes’ readings are employed for CS. We show that CBCA requires significantly less data transmission than the RC method with a little recovery accuracy loss. We also identify optimal parameters of CBCA via mathematical analysis and validate them by simulation. Finally, we used water level data collected from a real-world flood inundation monitoring system to drive our simulation experiments and showed the effectiveness of CBCA.
Auteurs: Kun-Chan Lan;Ming-Zhi Wei;
Apparue dans: IEEE Sensors Journal
Date publication: 04.-2017, volume: 17, issue:8, pages: 2550 - 2562
Editeur: IEEE
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» A Constrained Dual Kalman Filter Based on pdf Truncation for Estimation of Vehicle Parameters and Road Bank Angle: Analysis and Experimental Validation
Résumé:
Vehicles today are equipped with control systems that improve their handling and stability. Knowledge of road bank angle and vehicle parameters is crucial for good behavior in this type of control. This paper develops a new method for estimating different states, such as vehicle roll angle, road bank angle, and vehicle parameters. This method combines a dual Kalman filter with a probability density function truncation method to consider the parameter physical limitations. Experimental results show the effectiveness of the proposed method and demonstrate that the incorporation of parameter constraints improves its estimation accuracy. The proposed method provides an estimation of the parameters and the states' physical meaning and the stable values within the real boundary limits in contrast to other estimation methods.
Auteurs: Beatriz L. Boada;Daniel Garcia-Pozuelo;Maria Jesus L. Boada;Vicente Diaz;
Apparue dans: IEEE Transactions on Intelligent Transportation Systems
Date publication: 04.-2017, volume: 18, issue:4, pages: 1006 - 1016
Editeur: IEEE
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» A Contrarian History of Early Electric Power Distribution [Scanning Our Past]
Résumé:
A 1922 article in Electrical World designated Edison as the father of the central station industry [1]. Edison’s invention of practical incandescent electric lighting in 1879 was the driving force for the success of Edison’s commercial low-voltage short-range direct current (dc) transmission systems in the United States and elsewhere, beginning in 1882. However, in 1886, high-voltage long-range alternating current (ac) transmission systems of Ganz & Co. of Budapest began to compete with Edison’s dc systems in Europe, and ac systems of the Westinghouse Electric Co. began to compete with Edison’s dc systems in the United States. Edison reacted by reaching into the toolbox of politicians.
Auteurs: Adam Allerhand;
Apparue dans: Proceedings of the IEEE
Date publication: 04.-2017, volume: 105, issue:4, pages: 768 - 778
Editeur: IEEE
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» A Conversation with Your Future Self [From the Editor's Desk]
Résumé:
Presents the introductory editorial for this issue of the publication.
Auteurs: Lanny Floyd;
Apparue dans: IEEE Industry Applications Magazine
Date publication: 04.-2017, volume: 23, issue:2, pages: 3 - 3
Editeur: IEEE
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» A Convex Sum-of-Squares Approach to Analysis, State Feedback and Output Feedback Control of Parabolic PDEs
Résumé:
We present an optimization-based framework for analysis and control of linear parabolic partial differential equations (PDEs) with spatially varying coefficients without discretization or numerical approximation. For controller synthesis, we consider both full-state feedback and point observation (output feedback). The input occurs at the boundary (point actuation). We use positive-definite matrices to parameterize positive Lyapunov functions and polynomials to parameterize controller and observer gains. We use duality and an invertible state variable transformation to convexify the controller synthesis problem. Finally, we combine our synthesis condition with the Luenberger observer framework to express the output feedback controller synthesis problem as a set of LMI/SDP constraints. We perform an extensive set of numerical experiments to demonstrate the accuracy of the conditions and to prove the necessity of the Lyapunov structures chosen. We provide numerical and analytical comparisons with alternative approaches to control, including Sturm–Liouville theory and backstepping. Finally, we use numerical tests to show that the method retains its accuracy for alternative boundary conditions.
Auteurs: Aditya Gahlawat;Matthew M. Peet;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 04.-2017, volume: 62, issue:4, pages: 1636 - 1651
Editeur: IEEE
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» A Cooperative MIMO Radar Network Using Highly Integrated FMCW Radar Sensors
Résumé:
In this paper, an incoherent radar network based on integrated radar sensors is presented. It consists of radar sensor nodes with independently generated frequency-modulated continuous wave-modulated transmit signals, performing both monostatic and bistatic distance measurements. An architecture to operate such a cooperative bistatic network is introduced and an optimal parameterization of the system is presented. Several nonidealities of frequency synthesizers, that are important for such cooperative radar networks, are discussed and their influence on system performance is evaluated. A prototype of the cooperative bistatic network has been realized using highly integrated radar sensors at 122 GHz. Radar measurements using the prototype prove the feasibility and potential of the network approach. The complete signal processing chain is presented, including an adapted multilateration algorithm for target position estimation using all measured distances.
Auteurs: Andreas Frischen;Jürgen Hasch;Christian Waldschmidt;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 04.-2017, volume: 65, issue:4, pages: 1355 - 1366
Editeur: IEEE
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» A Correction to “Some Gabidulin Codes Cannot be List Decoded Efficiently at any Radius”
Résumé:
There is an error in the above titled paper [1]. As a result, the main statement of the paper is true for a subset of the Gabidulin codes for which it was initially stated. To be precise, our results on the list decodability still hold for the same parameters of n and m , but the evaluation points have to be of a certain structure.
Auteurs: Netanel Raviv;Antonia Wachter-Zeh;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 04.-2017, volume: 63, issue:4, pages: 2623 - 2624
Editeur: IEEE
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» A DC Bus Voltage Balancing Technique for the Cascaded H-Bridge STATCOM With Improved Reliability Under Grid Faults
Résumé:
As more distributed renewable energy sources are installed in the utility grid, the static synchronous compensators are applied to manage the power factor and the grid voltage in the medium-voltage level of the power system. The cascaded multilevel converter with single-star topology is well applied to this application. The dc-capacitor voltage balancing control is a fundamental issue, and it can be accomplished by negative-sequence current and/or zero sequence voltage injection. Unfortunately, the zero sequence voltage injection increases the risk of over-modulation and the negative-sequence current injection results in high peak current. This paper provides the voltage balancing strategy to manage the peak current or the modulation index. Besides, all the asymmetrical grid voltages are considered in the proposed method to satisfy the grid fault operation. Laboratory test results verify that the proposed method limits the peak current or manages the modulation index during the grid fault operations.
Auteurs: Hsin-Chih Chen;Po-Tai Cheng;
Apparue dans: IEEE Transactions on Industry Applications
Date publication: 04.-2017, volume: 53, issue:2, pages: 1263 - 1270
Editeur: IEEE
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» A DC-to-8.5 GHz 32 : 1 Analog Multiplexer for On-Chip Continuous-Time Probing of Single-Event Transients in a 65-nm CMOS
Résumé:
A multiplexer circuit that is capable of accessing 32 internal nodes for the continuous-time probing of signal waveforms is proposed. A chip has been fabricated with eight multiplexer instances and used in experiments for monitoring radiation-induced single-event transients in digital circuits. Pulses with a width of less than 100 ps and pulses over 1 V in height were observed for 230-MeV particle hits. Measurements show 8.5 GHz, −3-dB bandwidth, and a 1.92% total harmonic distortion for a 1-V input range, and a 6.58% total harmonic distortion for a 2-V input range. The measured dynamic range is nominally 26.5 dB.
Auteurs: Mladen Mitrović;Michael Hofbauer;Bernhard Goll;Kerstin Schneider-Hornstein;Robert Swoboda;Bernhard Steindl;Kay-Obbe Voss;Horst Zimmermann;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 377 - 381
Editeur: IEEE
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» A DC-to-Three-Phase Boost–Buck Inverter With Stored Energy Modulation and a Tiny DC-Link Capacitor
Résumé:
Three-phase voltage-source inverters typically feature a significant amount of dc energy storage to maintain a stiff dc bus. In these cases, the dc-link capacitor is sized to store enough energy to maintain several tens of cycles of ac output at the rated power. In this paper, we propose to reduce the size of the dc-link capacitor dramatically to store enough energy to provide just one high-frequency switching cycle of the ac output power. The dc bus is no longer stiff, and hence, classical sinusoidal pulse-width modulation cannot be used. However, the stored energy modulation (SEM) proposed herein synthesizes high-quality sinusoidal output voltage waveforms, even with such tiny dc-link capacitors. In SEM, the switching intervals of the interconnecting switches are carefully determined nonlinear functions of various operating parameters such as reactive component sizing, switching frequency, load levels, etc. This paper presents the analytical and detailed design development of the SEM approach along with circuit simulation, experimental results, and comparative evaluation of a dc-to-three-phase system example.
Auteurs: Mahima Gupta;Giri Venkataramanan;
Apparue dans: IEEE Transactions on Industry Applications
Date publication: 04.-2017, volume: 53, issue:2, pages: 1280 - 1288
Editeur: IEEE
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» A Decentralized Model Predictive Control for Operation of Multiple Distributed Generators in an Islanded Mode
Résumé:
The increasing penetration of distributed and renewable generation presents power systems with a challenge of accommodating multiple inverter-based generators. Distributed generators (DGs), capable of operating in the islanded mode, are often installed in microgrids. However, a control system for operating multiple DGs in the islanded mode using voltage-sourced converters is a real challenge under uncertainties in load parameters, unbalanced phase conditions, and transients. This paper proposes a novel approach to decentralized control of multiple DGs. This approach is based on a combination of a voltage controller using model predictive control and a fast current controller using a discrete-time sliding-mode controller for limiting the inverter currents under overload conditions. Performance of the proposed control system is compared with a robust servomechanism program controller. The proposed control strategy provides fast tracking, robustness, and fast transient recovery in voltage and current under: 1) short-circuit conditions; 2) load transients; and 3) unbalanced loads. Various scenarios including reference signal tracking and robustness against the load perturbations are considered. Results are presented and discussed.
Auteurs: Ahmad Tavakoli;Michael Negnevitsky;Kashem M. Muttaqi;
Apparue dans: IEEE Transactions on Industry Applications
Date publication: 04.-2017, volume: 53, issue:2, pages: 1466 - 1475
Editeur: IEEE
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» A Decision Support System for Cooperative Logistics
Résumé:
This paper specifies a cloud-based cooperative decision support system (DSS) that aims at integrating logistics management and decision support strategies for intermodal transportation systems. The proposed DSS is dedicated to synchronize different transportation means by using the modern information and communications technology tools and by taking into account environmental aspects. This paper describes the DSS cloud-based architecture and presents the procedure to be followed in order to design a DSS able to support decision makers in different logistic decision fields. The advantages of the proposed DSS are enlightened by specifying three main decision modules: cargo transport optimization, intelligent truck parking, and CO2 monitoring. Moreover, the applicability of the proposed DSS is described by specifying a DSS for the case study of the logistic network of the Trieste port (Italy), including the port, the inland terminal, and the highway connecting them. Some simulation campaigns are employed both to set the decision modules and evaluate the DSS application benefits.
Auteurs: Maria Pia Fanti;Giorgio Iacobellis;Massimiliano Nolich;Andrea Rusich;Walter Ukovich;
Apparue dans: IEEE Transactions on Automation Science and Engineering
Date publication: 04.-2017, volume: 14, issue:2, pages: 732 - 744
Editeur: IEEE
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» A Deployable High-Gain Antenna Bound for Mars: Developing a new folded-panel reflectarray for the first CubeSat mission to Mars.
Résumé:
This article describes the development of a deployable high-gain antenna (HGA) for the proposed Mars Cube One (MarCO) CubeSat mission to Mars. The antenna is a new folded-panel reflectarray (FPR) designed to fit on a 6U (10 ? 20 ? 34 cm<sup>3</sup>) CubeSat bus and support 8.425-GHz Mars-to-Earth telecommunications. The FPR provides a gain of 29.2 dBic with right-hand circular polarization (RHCP). Small stowage volume is a key advantage of the FPR design, as it only consumes ~4% of the usable spacecraft payload volume with a mass of less than 1 kg.
Auteurs: Richard E. Hodges;Nacer Chahat;Daniel J. Hoppe;Joseph D. Vacchione;
Apparue dans: IEEE Antennas and Propagation Magazine
Date publication: 04.-2017, volume: 59, issue:2, pages: 39 - 49
Editeur: IEEE
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» A Dielectric Low-Perturbation Field Scanner for Multi-Path Environments
Résumé:
Well-established solutions capable of scanning electromagnetic fields in anechoic environments essentially rely on the massive use of absorbers, in order to keep under check energy scattered by the metallic parts of an automatic positioning system. Solutions of this kind are convenient whenever the field to scan is the result of line-of-sight (LOS) propagation. In complex media, where multipath propagation imply non-LOS contributions, the introduction of absorbing materials can irremediably alter the behavior of the medium under test and therefore the field to be scanned. In this case, a field scanner rather needs to be as transparent as possible. This paper introduces the main ideas behind an alternative automatic positioning system designed in order to ensure a low perturbation of the response of a medium. The impact of the scanner is assessed when used in a reverberation chamber with a varying degree of reverberation, in order to emulate the conditions found in realistic complex media. Expected applications are mainly found in sounding propagation in complex media.
Auteurs: Andrea Cozza;Francesco Masciovecchio;Cécile Dorgan;Mohamed Serhir;Florian Monsef;Dominique Lecointe;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1978 - 1987
Editeur: IEEE
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» A Differential-Fed Microstrip Patch Antenna With Bandwidth Enhancement Under Operation of TM10 and TM30 Modes
Résumé:
A differential-fed microstrip patch antenna (MPA) with bandwidth enhancement is proposed under the operation of TM10 and TM30 resonant modes in a single patch resonator. Initially, a rectangular differential-fed MPA is theoretically investigated so as to demonstrate that all of the undesired modes between the TM10 and TM30 modes are suppressed or removed out effectively. Then, by symmetrically introducing two pairs of shorting pins, the resonant frequency of TM10 mode is progressively turned up. After that, with the help of two long slots, the resonant frequency of TM30 mode is decreased with slight effect on that of TM10 mode. Furthermore, a short slot is inserted at the center of the patch to cancel the parasitic inductances of the shorting pins and probe feeds. With this arrangement, these two radiative resonant modes are moved in proximity to each other for wideband antenna. Finally, the proposed differential-fed MPA is fabricated and measured. Experimental results illustrate that the impedance bandwidth ( $vert S_{{{text {dd}11}}}vert < -10$ dB) of the antenna has gained a tremendous increment up to about 13% (1.88–2.14 GHz), while keeping a low profile property with the height of 0.029 free-space wavelength. Additionally, the antenna has achieved a stable gain varied from 5.8 to 7 dBi over the operating band.
Auteurs: Neng-Wu Liu;Lei Zhu;Wai-Wa Choi;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1607 - 1614
Editeur: IEEE
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» A Digital Method of Power-Sharing and Cross-Regulation Suppression for Single-Inductor Multiple-Input Multiple-Output DC–DC Converter
Résumé:
This paper presents a digital method to regulate the single-inductor multiple-input multiple-output (SI-MIMO) dc-dc converter, which can integrate renewable sources and loads as the hybrid renewable energy system with less components. The digital method is able to achieve power-sharing and cross-regulation suppression, and it is named as PS-CRS. PS-CRS is based on model predictive control, power sharing, and time multiplexing. A power-sharing controller is developed to regulate the power from multiple power sources. A cross-regulation-suppression controller is designed to control the output voltages independently with reduced cross regulation, which is the critical issue of the single-inductor multiple-output dc-dc converter. Experimental prototype of a single-inductor dual-input dual-output buck converter is built for verification. The steady-state operation and dynamic performance cases are studied. The results demonstrate that PS-CRS is able to regulate the SI-MIMO dc-dc converter effectively and robustly.
Auteurs: Benfei Wang;Liang Xian;Venkata Ravi Kishore Kanamarlapudi;King Jet Tseng;Abhisek Ukil;Hoay Beng Gooi;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 2836 - 2847
Editeur: IEEE
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» A Distributed Green Networking Approach for Data Center Networks
Résumé:
Green networking for data center network is becoming a critical issue due to the rapid growth of energy consumption. Most of existing green networking approaches are in a centralized-control manner, which have a scalability issue. Existing distributed approaches are scalable, but consume too much network resource, including computing and network bandwidth. In this letter, we propose a distributed green networking approach for data center network, called distributed green networking approach (DGNA). In our approach, we propose an energy-efficient flow scheduling mechanism, which requires less computing and much less network bandwidth compared with traditional approaches. In DGNA, two shut-off algorithms are proposed to shut-off links with different efficiency and complexity. Simulation shows that DGNA sends less than 0.9% of link state advertisements compared with a traditional approach.
Auteurs: Qin-Liang Lin;Shun-Zheng Yu;
Apparue dans: IEEE Communications Letters
Date publication: 04.-2017, volume: 21, issue:4, pages: 797 - 800
Editeur: IEEE
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» A Driver State Detection System—Combining a Capacitive Hand Detection Sensor With Physiological Sensors
Résumé:
With respect to automotive safety, the driver plays a crucial role. Stress level, tiredness, and distraction of the driver are therefore of high interest. In this paper, a driver state detection system based on cellular neural networks (CNNs) to monitor the driver's stress level is presented. We propose to include a capacitive-based wireless hand detection (position and touch) sensor for a steering wheel utilizing ink-jet printed sensor mats as an input sensor in order to improve the performance. A driving simulator platform providing a realistic virtual traffic environment is utilized to conduct a study with 22 participants for the evaluation of the proposed system. Each participant is driving in two different scenarios, each representing one of the two no-stress/stress driver states. A “threefold” cross validation is applied to evaluate our concept. The subject dependence is considered carefully by separating the training and testing data. Furthermore, the CNN approach is benchmarked against other state-of-the-art machine learning techniques. The results show a significant improvement combining sensor inputs from different driver inherent domains, giving a total related detection accuracy of 92%. Besides that, this paper shows that in case of including the capacitive hand detection sensor, the accuracy increases by 10%. These findings indicate that adding a subject-independent sensor, such as the proposed capacitive hand detection sensor, can significantly improve the detection performance.
Auteurs: Stephan Mühlbacher-Karrer;Ahmad Haj Mosa;Lisa-Marie Faller;Mouhannad Ali;Raiyan Hamid;Hubert Zangl;Kyandoghere Kyamakya;
Apparue dans: IEEE Transactions on Instrumentation and Measurement
Date publication: 04.-2017, volume: 66, issue:4, pages: 624 - 636
Editeur: IEEE
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» A Fast Estimation Technique for Evaluating the Specific Absorption Rate of Multiple-Antenna Transmitting Devices
Résumé:
In this paper, we present a fast technique for estimating the specific absorption rate (SAR) of multiple-antenna transmitting devices such as mobile phones, which utilize two or more antennas in communication. SAR values for arbitrary relative phase combinations of the antennas at an observation point can be estimated from SAR measurements for several known relative phases at the same observation point. Several numerical and experimental validations on different antenna configurations and operating frequencies have been carried out to verify the proposed estimation method. It has been highlighted that the proposed estimation method is simple yet provides highly accurate estimated SAR values.
Auteurs: Dinh Thanh Le;Lira Hamada;Soichi Watanabe;Teruo Onishi;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1947 - 1957
Editeur: IEEE
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» A Feasibility Study of Broadband White Light Emitting Diode (WLED) Based Full-Field Optical Coherence Microscopy (FF-OCM) Using Derivative-Based Algorithm
Résumé:
Developing cost-effective and fast detection methods in full-field optical coherence microscopy (FF-OCM) platform for biological applications is of prime focus today. In this paper, we report a cost-effective Linnik type FF-OCM system with a single broadband white light emitting diode (WLED) (470–850 nm, λ0 = 630 nm) light source in conjunction with a derivative-based image reconstruction algorithm. Sequential 2-D multiple phase-shifted interferograms were obtained by moving the sample stage using piezoelectric transducer and recorded via a 2-D charge complementary oxide semiconductor camera. Subsequently, the en-face sectional images were reconstructed using a derivative-based algorithm. The measured axial and lateral resolutions along with interferometric phase stability of the system were 0.9 μm, 1.4 μm, and 11 mrad, respectively. The advantages of the derivative-based algorithm over 4-step phase shifted method were demonstrated using USAF target and onion as test samples. Moreover, studies via the present system of the microstructure of skin epidermis in mouse ear with melanoma showed a significant deterioration from normal mouse skin in stratum corneum of the epidermis. This is the first study of the application of a derivative-based algorithm for biological samples in FF-OCM wherein WLED is used as a light source. The present system is stable, compact, and cost-effective compared to the conventional FF-OCM systems and provides comparable spatial resolution.
Auteurs: Tulsi Anna;Ting-Wei Chang;Chih-Ming Lai;Arthur Chiou;Wen-Chuan Kuo;
Apparue dans: IEEE Photonics Journal
Date publication: 04.-2017, volume: 9, issue:2, pages: 1 - 13
Editeur: IEEE
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» A Flexible Computational Framework Using R and Map-Reduce for Permutation Tests of Massive Genetic Analysis of Complex Traits
Résumé:
In quantitative trait locus (QTL) mapping significance of putative QTL is often determined using permutation testing. The computational needs to calculate the significance level are immense, $10^4$ up to $10^8$ or even more permutations can be needed. We have previously introduced the PruneDIRECT algorithm for multiple QTL scan with epistatic interactions. This algorithm has specific strengths for permutation testing. Here, we present a flexible, parallel computing framework for identifying multiple interacting QTL using the PruneDIRECT algorithm which uses the map-reduce model as implemented in Hadoop. The framework is implemented in R, a widely used software tool among geneticists. This enables users to rearrange algorithmic steps to adapt genetic models, search algorithms, and parallelization steps to their needs in a flexible way. Our work underlines the maturity of accessing distributed parallel computing for computationally demanding bioinformatics applications through building workflows within existing scientific environments. We investigate the PruneDIRECT algorithm, comparing its performance to exhaustive search and DIRECT algorithm using our framework on a public cloud resource. We find that PruneDIRECT is vastly superior for permutation testing, and perform $2 times 10^5$ permutations for a 2D QTL problem in $15$ hours, using $100$ cloud processes. We show that our framework scales out almost linearly for a 3D QTL search.
Auteurs: Behrang Mahjani;Salman Toor;Carl Nettelblad;Sverker Holmgren;
Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Date publication: 04.-2017, volume: 14, issue:2, pages: 381 - 392
Editeur: IEEE
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» A Force Compensation Approach Toward Divergence of Hardware-in-the-Loop Contact Simulation System for Damped Elastic Contact
Résumé:
The simulation of contact process of flying objects in space is important for many space missions. The hardware-in-the-loop (HIL) simulation is an attractive approach because it integrates the fidelity of physical simulation and the flexibility of numerical simulation. But the HIL contact simulation is divergent due to the time delay, e.g., the dynamic response delay and the force measurement delay. In this study, a force compensation approach is proposed toward the HIL simulation divergence problem for the damped and elastic contact. The idea is to make the compensated force close to the ideal force corresponding to the numerical position computed from the dynamics model of flying objects. The approach includes the phase lead based force compensation for the force measurement delay, and the response error based force compensation for the dynamic response delay of the motion simulator. From simulations and experiments, it is shown that the proposed approach can effectively and satisfactorily compensate the simulation divergence.
Auteurs: Chenkun Qi;Feng Gao;Xianchao Zhao;Anye Ren;Qian Wang;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 2933 - 2943
Editeur: IEEE
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» A Framework of Automatic Clustering and Tracking for Time-Variant Multipath Components
Résumé:
A framework of automatic clustering and tracking algorithm is proposed for the multipath components (MPCs) in time-variant radio channels. The algorithm is based on the channel dynamics in time domain and is able to reflect the birth and death behaviors of MPCs naturally. The proposed algorithm is validated by a ray-tracer and the spatial channel model extension simulations. Compared with other existing clustering algorithms, the proposed framework is able to cluster the time-varying MPCs and track the clusters with high accuracy and low complexity.
Auteurs: Qi Wang;Bo Ai;Ruisi He;Ke Guan;Yan Li;Zhangdui Zhong;Guowei Shi;
Apparue dans: IEEE Communications Letters
Date publication: 04.-2017, volume: 21, issue:4, pages: 953 - 956
Editeur: IEEE
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» A Front-End ASIC With Receive Sub-array Beamforming Integrated With a $32 times 32$ PZT Matrix Transducer for 3-D Transesophageal Echocardiography
Résumé:
This paper presents a power- and area-efficient front-end application-specific integrated circuit (ASIC) that is directly integrated with an array of $32 times 32$ piezoelectric transducer elements to enable next-generation miniature ultrasound probes for real-time 3-D transesophageal echocardiography. The $6.1 times 6.1$ mm2 ASIC, implemented in a low-voltage 0.18- $mu text{m}$ CMOS process, effectively reduces the number of receive (RX) cables required in the probe’s narrow shaft by ninefold with the aid of 96 delay-and-sum beamformers, each of which locally combines the signals received by a sub-array of $3 times 3$ elements. These beamformers are based on pipeline-operated analog sample-and-hold stages and employ a mismatch-scrambling technique to prevent the ripple signal associated with the mismatch between these stages from limiting the dynamic range. In addition, an ultralow-power low-noise amplifier architecture is proposed to increase the power efficiency of the RX circuitry. The ASIC has a compact element matched layout and consumes only 0.27 mW/channel while receiving, which is lower than the state-of-the-art circuit. Its functionality has been successfully demonstrated in 3-D imaging experiments.
Auteurs: Chao Chen;Zhao Chen;Deep Bera;Shreyas B. Raghunathan;Maysam Shabanimotlagh;Emile Noothout;Zu-Yao Chang;Jacco Ponte;Christian Prins;Hendrik J. Vos;Johan G. Bosch;Martin D. Verweij;Nico de Jong;Michiel A. P. Pertijs;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 994 - 1006
Editeur: IEEE
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» A Fuzzy Control Model for Restraint of Bullwhip Effect in Uncertain Closed-Loop Supply Chain With Hybrid Recycling Channels
Résumé:
By considering the uncertainties in the closed-loop supply chain system with hybrid recycling channels, a fuzzy control model is constructed to restrain the bullwhip effect. Firstly, the basic models of the uncertain closed-loop supply chain with hybrid recycling channels are established where the manufacturer and the third party recovery provider collect the recycled products at the same time. Then, the basic models of the closed-loop supply chain are converted into a nonlinear fuzzy switching model based on the discrete Takagi–Sugeno (T–S) fuzzy control system. Secondly, a fuzzy robust control method is utilized to reduce the impacts caused by the internal and external uncertain factors on the closed-loop supply chain. This method can not only restrain the bullwhip effect, but also make supply chain remain robust stability. Finally, the simulation results show the feasibility and effectiveness of the constructed fuzzy control system.
Auteurs: Songtao Zhang;Xue Li;Chunyang Zhang;
Apparue dans: IEEE Transactions on Fuzzy Systems
Date publication: 04.-2017, volume: 25, issue:2, pages: 475 - 482
Editeur: IEEE
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» A Game-Theoretic Framework for Network Coding Based Device-to-Device Communications
Résumé:
This paper investigates the delay minimization problem for instantly decodable network coding (IDNC) based device-to-device (D2D) communications. In D2D enabled systems, users cooperate to recover all their missing packets. The paper proposes a game theoretic framework as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. The session is modeled by self-interested players in a non-cooperative potential game. The utility functions are designed so as increasing individual payoff results in a collective behavior which achieves both a desirable system performance in a shared network environment and the Nash equilibrium. Three games are developed whose first reduces the completion time, the second the maximum decoding delay and the third the sum decoding delay. The paper, further, improves the formulations by including a punishment policy upon collision occurrence so as to achieve the Nash bargaining solution. Learning algorithms are proposed for systems with complete and incomplete information, and for the imperfect feedback scenario. Numerical results suggest that the proposed game-theoretical formulation provides appreciable performance gain against the conventional point-to-multipoint (PMP), especially for reliable user-to-user channels.
Auteurs: Ahmed Douik;Sameh Sorour;Hamidou Tembine;Tareq Y. Al-Naffouri;Mohamed-Slim Alouini;
Apparue dans: IEEE Transactions on Mobile Computing
Date publication: 04.-2017, volume: 16, issue:4, pages: 901 - 917
Editeur: IEEE
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» A General and Accurate Formula for the Beamwidth of 1-D Leaky-Wave Antennas
Résumé:
In this paper, a general formula for the half-power beamwidth of one-dimensional leaky-wave antennas (1-D LWAs) is presented. With respect to previous beamwidth formulas found in the literature, the new formula allows for both arbitrary propagation wavenumber and length of the antenna. The pointing angle of the beam is allowed to be arbitrary, and may be near broadside or endfire, or any angle in between. The beamwidth is also allowed to be arbitrary, though a simpler approximate expression is obtained under the assumption of a narrow beam. Numerical results confirm the accuracy of the new beamwidth formula. Furthermore, it is shown that the previous existing formulas are approximate limiting cases of this more general result. This new formula will provide a very useful tool for obtaining more reliable results for the beamwidth of any type of 1-D LWA.
Auteurs: Walter Fuscaldo;David R. Jackson;Alessandro Galli;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1670 - 1679
Editeur: IEEE
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» A Generic Method for Accelerating LSH-Based Similarity Join Processing
Résumé:
Locality sensitive hashing (LSH) is an efficient method for solving the problem of approximate similarity search in high-dimensional spaces. Through LSH, a high-dimensional similarity join can be processed in the same way as hash join, making the cost of joining two large datasets linear. By judicially analyzing the properties of multiple LSH algorithms, we propose a generic method to speed up the process of joining two large datasets using LSH. The crux of our method lies in the way which we identify a set of representative points to reduce the number of LSH lookups. Theoretical analyzes show that our proposed method can greatly reduce the number of lookup operations and retain the same result accuracy compared to executing LSH lookups for every query point. Furthermore, we demonstrate the generality of our method by showing that the same principle can be applied to LSH algorithms for three different metrics: the Euclidean distance (QALSH), Jaccard similarity measure (MinHash), and Hamming distance (sequence hashing). Results from experimental studies using real datasets confirm our error analyzes and show significant improvements of our method over the state-of-the-art LSH method: to achieve over 0.95 recall, we only need to operate LSH lookups for at most 15 percent of the query points.
Auteurs: Chenyun Yu;Sarana Nutanong;Hangyu Li;Cong Wang;Xingliang Yuan;
Apparue dans: IEEE Transactions on Knowledge and Data Engineering
Date publication: 04.-2017, volume: 29, issue:4, pages: 712 - 726
Editeur: IEEE
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» A Geometry-Aware Domain Decomposition Preconditioning for Hybrid Finite Element-Boundary Integral Method
Résumé:
Fast, scalable, and robust solution of the hybrid finite element-boundary integral (FE-BI) linear system of equations is traditionally considered a challenge due to multifaceted technical difficulties. This paper proposes a nonoverlapping geometry-aware domain decomposition (DD) preconditioning technique for iteratively solving hybrid FE-BI equation. The technique ingredients include a volume-based Schwarz FE DD method and a surface-based interior penalty BI DD method. Compared with previous algorithms, the work has two major benefits: 1) it results in a robust and cost-effective preconditioning technique for the solution of the FE-BI linear system of equations and 2) it provides a flexible and natural way to set up the mathematical models, to create the problem geometries, and to discretize the computational domain. The capability and performance of the computational algorithms are illustrated and validated through numerical experiments.
Auteurs: Hong-Wei Gao;Zhen Peng;Xin-Qing Sheng;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 04.-2017, volume: 65, issue:4, pages: 1875 - 1885
Editeur: IEEE
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» A Geometry-Based Underwater Acoustic Channel Model Allowing for Sloped Ocean Bottom Conditions
Résumé:
This paper proposes a new geometry-based channel model for shallow-water ocean environments, in which the ocean bottom can slope gently down/up. The need for developing such an underwater acoustic (UWA) channel model is driven by the fact that the standard assumption of a flat ocean bottom does not hold in many realistic scenarios. Starting from a geometrical model, we develop a stochastic channel model for wideband single-input single-output vehicle-to-vehicle UWA channels using the ray theory assuming smooth ocean surface and bottom. We investigate the effect of the ocean-bottom slope angle on the distribution of the channel envelope, instantaneous channel capacity, temporal autocorrelation function, frequency correlation function, Doppler power spectral density, and the power delay profile. Theoretical and simulation results show that even a relatively small slope angle influences considerably the statistical properties of UWA channels. The validation of the proposed UWA channel model has been performed by fitting its main characteristic quantities (average delay, delay spread, and coherence bandwidth) to measurement data. In comparison with the conventional UWA channel model, which has been developed on the assumption of a flat ocean bottom, it is shown that the proposed UWA channel model enables the modeling of measured channels with higher precision.
Auteurs: Meisam Naderi;Matthias Pätzold;Rym Hicheri;Néji Youssef;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 04.-2017, volume: 16, issue:4, pages: 2394 - 2408
Editeur: IEEE
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» A Global Expectation–Maximization Approach Based on Memetic Algorithm for Vibration-Based Structural Damage Detection
Résumé:
This paper proposes a novel unsupervised damage detection approach based on a memetic algorithm that establishes the normal or undamaged condition of a structural system as data clusters through a global expectation-maximization technique, using only damage-sensitive features extracted from output-only vibration measurements. The health state is then discriminated by considering the Mahalanobis squared distance between the learned clusters and a new observation. The proposed approach is compared with state-of-the-art ones by taking into account real-world data sets from the Z-24 Bridge (Switzerland), where several damage scenarios were performed. The results indicated that the proposed approach can be applied in structural health monitoring applications where life safety, economic, and reliability issues are the most important motivations to consider.
Auteurs: Adam Santos;Reginaldo Santos;Moisés Silva;Eloi Figueiredo;Claudomiro Sales;João C. W. A. Costa;
Apparue dans: IEEE Transactions on Instrumentation and Measurement
Date publication: 04.-2017, volume: 66, issue:4, pages: 661 - 670
Editeur: IEEE
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» A GPU-Accelerated 3-D Coupled Subsample Estimation Algorithm for Volumetric Breast Strain Elastography
Résumé:
Our primary objective of this paper was to extend a previously published 2-D coupled subsample tracking algorithm for 3-D speckle tracking in the framework of ultrasound breast strain elastography. In order to overcome heavy computational cost, we investigated the use of a graphic processing unit (GPU) to accelerate the 3-D coupled subsample speckle tracking method. The performance of the proposed GPU implementation was tested using a tissue-mimicking phantom and in vivo breast ultrasound data. The performance of this 3-D subsample tracking algorithm was compared with the conventional 3-D quadratic subsample estimation algorithm. On the basis of these evaluations, we concluded that the GPU implementation of this 3-D subsample estimation algorithm can provide high-quality strain data (i.e., high correlation between the predeformation and the motion-compensated postdeformation radio frequency echo data and high contrast-to-noise ratio strain images), as compared with the conventional 3-D quadratic subsample algorithm. Using the GPU implementation of the 3-D speckle tracking algorithm, volumetric strain data can be achieved relatively fast (approximately 20 s per volume [2.5 cm $times2.5$ cm $times2.5$ cm]).
Auteurs: Bo Peng;Yuqi Wang;Timothy J. Hall;Jingfeng Jiang;
Apparue dans: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Date publication: 04.-2017, volume: 64, issue:4, pages: 694 - 705
Editeur: IEEE
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» A Hierarchical Decision-Making Strategy for the Energy Management of Smart Cities
Résumé:
This paper presents a hierarchical decision-making strategy for the energy management of a smart city. The proposed decision process supports the city energy manager and local policy makers in taking energy retrofit decisions on different urban sectors by an integrated, structured, and transparent management. To this aim, in the proposed decision strategy, a bilevel programming model integrates several local decision-making units, each focusing on the energy retrofit optimization of a specific urban subsystem, and a central decision unit. We solve the hierarchical decision problem by a game theoretic distributed algorithm. We apply the developed decision model to the case study of the city of Bari (Italy), where a smart city program has recently been launched.
Auteurs: Raffaele Carli;Mariagrazia Dotoli;Roberta Pellegrino;
Apparue dans: IEEE Transactions on Automation Science and Engineering
Date publication: 04.-2017, volume: 14, issue:2, pages: 505 - 523
Editeur: IEEE
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» A High Deposition Rate Amorphous-Silicon Process for Use as a Thick Sacrificial Layer in Surface-Micromachining
Résumé:
Amorphous and polycrystalline silicon are commonly used as sacrificial layers in the surface micromachining of microelectromechanical systems (MEMS) devices, because they have high thickness uniformity over a large wafer area, and a similar coefficient of thermal expansion to suspended structural materials such as silicon nitride and silicon oxide. However, the low deposition rate of amorphous-silicon hinders its application in devices that require a suspension gap greater than several micrometres, and chemical stability can be an issue. This paper addresses these issues through the development of a high deposition rate hydrogenated amorphous silicon thin film process. We have demonstrated two unique processing regimes, which can support either a low or high temperature process. The low-temperature processes can be used to deposit silicon thin films at temperatures fromroom temperature up to 100°C, with deposition rates as high as 0.2 $mu text{m}$ /min. The high-temperature recipes, deposited at temperatures at and above 200°C, have a slightly lower deposition rate of 0.14 $mu text{m}$ /min, but are found to be chemically resistant to etching in positive photoresist developer. [2016-0273]
Auteurs: Michal Zawierta;Mariusz Martyniuk;Roger D. Jeffery;Gino Putrino;Adrian Keating;K. K. M. B. Dilusha Silva;Lorenzo Faraone;
Apparue dans: Journal of Microelectromechanical Systems
Date publication: 04.-2017, volume: 26, issue:2, pages: 406 - 414
Editeur: IEEE
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» A High-Efficiency 6.78-MHz Full Active Rectifier With Adaptive Time Delay Control for Wireless Power Transmission
Résumé:
This paper presents a full active rectifier consisting of GaN devices and a CMOS controller designed for wireless power transmission in high-power consumer devices. An adaptive time delay control circuit is developed to maximize the conduction interval of the GaN switch, which can significantly reduce the power loss caused by the forward voltage imposed by the diode. The proposed control algorithm also eliminates the reverse leakage current of the rectifier, and thus further improves its power transfer efficiency. The controller implemented based on a high-voltage 0.18- \mu text{m} CMOS process and the power stage consisting of four GaN transistors are assembled on the same printed circuit board (PCB) board. The proposed rectifier provides a maximum output current of 3 A at 5 V, with a 6.78-MHz ac input voltage. Its peak power transfer efficiency is 91.8%.
Auteurs: Xiaoyin Bai;Zhi-Hui Kong;Liter Siek;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 04.-2017, volume: 25, issue:4, pages: 1297 - 1306
Editeur: IEEE
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» A High-Linearity Wideband Common-Gate LNA With a Differential Active Inductor
Résumé:
A capacitor cross-coupled (CCC) wideband common-gate low-noise amplifier (CGLNA) with improved linearity and frequency response is presented. A novel differential active inductor (AI) is designed to improve the in-band gain flatness and high-frequency gain using the gate-inductive gain-peaking technique. The AI prevents the small-signal current flowing to the ground through the gate–drain capacitors. The CCC technique improves noise performance and saves power. However, it will also increase nonlinear distortions due to the boosted signal amplitude. To overcome the CCC-induced linearity deterioration, the derivative superposition technique is employed by using two parallel input transistors biased at different regions. The measurement results of the fabricated prototype in a 0.18- $mutext{m}$ CMOS process show that the voltage gain, the minimum noise figure, and the third-order intercept point are 16.9 dB, 2.5 dB, and 5.5 dBm, respectively, within the 3-dB bandwidth from 100 MHz to 1.45 GHz. The CGLNA consumes 9.3 mW from a 1.8-V supply and the active area is $0.29times 0.26 text{mm}^{2}$.
Auteurs: Li Ma;Zhi-Gong Wang;Jian Xu;N. M. Amin;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 402 - 406
Editeur: IEEE
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» A High-Performance Neural Prosthesis Incorporating Discrete State Selection With Hidden Markov Models
Résumé:
Communication neural prostheses aim to restore efficient communication to people with motor neurological injury or disease by decoding neural activity into control signals. These control signals are both analog (e.g., the velocity of a computer mouse) and discrete (e.g., clicking an icon with a computer mouse) in nature. Effective, high-performing, and intuitive-to-use communication prostheses should be capable of decoding both analog and discrete state variables seamlessly. However, to date, the highest-performing autonomous communication prostheses rely on precise analog decoding and typically do not incorporate high-performance discrete decoding. In this report, we incorporated a hidden Markov model (HMM) into an intracortical communication prosthesis to enable accurate and fast discrete state decoding in parallel with analog decoding. In closed-loop experiments with nonhuman primates implanted with multielectrode arrays, we demonstrate that incorporating an HMM into a neural prosthesis can increase state-of-the-art achieved bitrate by 13.9% and 4.2% in two monkeys ( p < 0.01 ). We found that the transition model of the HMM is critical to achieving this performance increase. Further, we found that using an HMM resulted in the highest achieved peak performance we have ever observed for these monkeys, achieving peak bitrates of 6.5 , 5.7 , and 4.7  bps in Monkeys J, R, and L, respectively. Finally, we found that this neural prosthesis was robustly controllable for the duration of entire experimental sess ons. These results demonstrate that high-performance discrete decoding can be beneficially combined with analog decoding to achieve new state-of-the-art levels of performance.
Auteurs: Jonathan C. Kao;Paul Nuyujukian;Stephen I. Ryu;Krishna V. Shenoy;
Apparue dans: IEEE Transactions on Biomedical Engineering
Date publication: 04.-2017, volume: 64, issue:4, pages: 935 - 945
Editeur: IEEE
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» A Highly Efficient and Reliable Inverter Configuration Based Cascaded Multilevel Inverter for PV Systems
Résumé:
This paper presents an improved cascaded multilevel inverter (CMLI) based on a highly efficient and reliable configuration for the minimization of the leakage current. Apart from a reduced switch count, the proposed scheme has additional features of low switching and conduction losses. The proposed topology with the given pulse width modulation (PWM) technique reduces the high-frequency voltage transitions in the terminal and common-mode voltages. Avoiding high-frequency voltage transitions achieves the minimization of the leakage current and reduction in the size of electromagnetic interference filters. Furthermore, the extension of the proposed CMLI along with the PWM technique for 2m + 1 levels is also presented, where m represents the number of photovoltaic (PV) sources. The proposed PWM technique requires only a single carrier wave for all 2m + 1 levels of operation. The total harmonic distortion of the grid current for the proposed CMLI meets the requirements of IEEE 1547 standard. A comparison of the proposed CMLI with the existing PV multilevel inverter topologies is also presented in the paper. Complete details of the analysis of PV terminal and common-mode voltages of the proposed CMLI using switching function concept, simulations, and experimental results are presented in the paper.
Auteurs: Sachin Jain;Venu Sonti;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 2865 - 2875
Editeur: IEEE
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» A History of Baseball and Paper Mills [History]
Résumé:
On Saturday night, 22 October 2016, I witnessed the Chicago Cubs clinch a place in baseball's 2016 World Series after capturing the pennant during the National League Central Division playoffs with the Los Angeles Dodgers. Not since 1945 had this baseball club been able to accomplish this extraordinary feat. It was on 28 May 1957, at a National League baseball owners midseason meeting in Chicago, that the decision was made to move the Brooklyn Dodgers franchise to Los Angeles. Chicago, of course, has always been known as a baseball town, and the young Cubs players, in their early 20s, magically captured the hearts of their devoted fans in winning their place in history once again.
Auteurs: Barry C. Brusso;
Apparue dans: IEEE Industry Applications Magazine
Date publication: 04.-2017, volume: 23, issue:2, pages: 7 - 11
Editeur: IEEE
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» A Hybrid Approach for Facial Performance Analysis and Editing
Résumé:
As of today, fine-grained editing of facial performances in movie and video production requires either retouching every single frame or creating a highly detailed CGI model of the actor, both of which is restricted to high-budget productions. In this paper, we present an example-based approach for facial performance editing that achieves realistic results with standard equipment and very little manual intervention. Based on a model-free surface tracking approach, temporally consistent dynamic texture sequences are extracted from multiple video streams. Using such geometry-plus-texture sequences allows transferring facial expressions/performances between videos, which enables the editor, for example, to change the facial expression while leaving the rest of the video untouched. Moreover, concatenating and/or looping these sequences in a motion-graph-like manner offers a convenient way of composing novel facial performances from multiple source videos. Finally, we present a blending method to seamlessly concatenate texture/mesh sequences and to insert a composed facial performance in a target video.
Auteurs: Wolfgang Paier;Markus Kettern;Anna Hilsmann;Peter Eisert;
Apparue dans: IEEE Transactions on Circuits and Systems for Video Technology
Date publication: 04.-2017, volume: 27, issue:4, pages: 784 - 797
Editeur: IEEE
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» A Hybrid Approach for the Sudoku Problem: Using Constraint Programming in Iterated Local Search
Résumé:
Sudoku is not only a popular puzzle but also an interesting and challenging constraint satisfaction problem. Therefore, automatic solving methods have been the subject of several publications in the past two decades. Although current methods provide good solutions for small-sized puzzles, larger instances remain challenging. This article introduces a new local search technique based on the min-conflicts heuristic for Sudoku. Furthermore, the authors propose an innovative hybrid search technique that exploits constraint programming as a perturbation technique within the iterated local search framework. They experimentally evaluate their methods on challenging benchmarks for Sudoku and report improvements over state-of-the-art solutions. To show the generalizability of the proposed approach, they also applied their method on another challenging scheduling problem. The results show that the proposed method is also robust in another problem domain.
Auteurs: Nysret Musliu;Felix Winter;
Apparue dans: IEEE Intelligent Systems
Date publication: 04.-2017, volume: 32, issue:2, pages: 52 - 62
Editeur: IEEE
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» A Hybrid CMOS-Memristor Neuromorphic Synapse
Résumé:
Although data processing technology continues to advance at an astonishing rate, computers with brain-like processing capabilities still elude us. It is envisioned that such computers may be achieved by the fusion of neuroscience and nano-electronics to realize a brain-inspired platform. This paper proposes a high-performance nano-scale Complementary Metal Oxide Semiconductor (CMOS)-memristive circuit, which mimics a number of essential learning properties of biological synapses. The proposed synaptic circuit that is composed of memristors and CMOS transistors, alters its memristance in response to timing differences among its pre- and post-synaptic action potentials, giving rise to a family of Spike Timing Dependent Plasticity (STDP). The presented design advances preceding memristive synapse designs with regards to the ability to replicate essential behaviours characterised in a number of electrophysiological experiments performed in the animal brain, which involve higher order spike interactions. Furthermore, the proposed hybrid device CMOS area is estimated as 600 \mu {text{m}}^2 in a 0.35 \mu {text{m}} process—this represents a factor of ten reduction in area with respect to prior CMOS art. The new design is integrated with silicon neurons in a crossbar array structure amenable to large-scale neuromorphic architectures and may pave the way for future neuromorphic systems with spike timing-dependent learning features. These systems are emerging for deployment in various applications ranging from basic neuroscience research, to pattern recognition, to Brain-Machine-Interfaces.
Auteurs: Mostafa Rahimi Azghadi;Bernabe Linares-Barranco;Derek Abbott;Philip H. W. Leong;
Apparue dans: IEEE Transactions on Biomedical Circuits and Systems
Date publication: 04.-2017, volume: 11, issue:2, pages: 434 - 445
Editeur: IEEE
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» A Hybrid Data Compression Scheme for Power Reduction in Wireless Sensors for IoT
Résumé:
This paper presents a novel data compression and transmission scheme for power reduction in Internet-of-Things (IoT) enabled wireless sensors. In the proposed scheme, data is compressed with both lossy and lossless techniques, so as to enable hybrid transmission mode, support adaptive data rate selection and save power in wireless transmission. Applying the method to electrocardiogram (ECG), the data is first compressed using a lossy compression technique with a high compression ratio (CR). The residual error between the original data and the decompressed lossy data is preserved using entropy coding, enabling a lossless restoration of the original data when required. Average CR of 2.1 \times and 7.8 \times were achieved for lossless and lossy compression respectively with MIT/BIH database. The power reduction is demonstrated using a Bluetooth transceiver and is found to be reduced to 18% for lossy and 53% for lossless transmission respectively. Options for hybrid transmission mode, adaptive rate selection and system level power reduction make the proposed scheme attractive for IoT wireless sensors in healthcare applications.
Auteurs: Chacko John Deepu;Chun-Huat Heng;Yong Lian;
Apparue dans: IEEE Transactions on Biomedical Circuits and Systems
Date publication: 04.-2017, volume: 11, issue:2, pages: 245 - 254
Editeur: IEEE
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» A Hybrid Resonant Pulse-Width Modulation Bridgeless AC–DC Power Factor Correction Converter
Résumé:
A hybrid resonant pulse-width modulation (PWM) bridgeless ac–dc power factor correction (PFC) boost converter is proposed for application in power supplies and battery chargers. The bridgeless operation of the proposed converter eliminates the need for the front-end diode bridge rectifier. The PWM switches share the same gating signal, so the converter does not need extra circuitry to sense the positive or negative ac input line-cycle operation. The resonant tank components are relatively small in size and, unlike a totem-pole PFC converter, the hybrid-resonant mode of operation alleviates the reverse-recovery losses for the body diodes of the PWM switches. The inherent inrush current-limiting capabilities improve the system reliability. Moreover, the converter architecture enables simple implementation of lightning and surge protection systems. To verify the proof of concept, experimental results are presented for a 650-W prototype at 70-kHz switching frequency, universal ac input, and 400-V dc output.
Auteurs: Muntasir Alam;Wilson Eberle;Deepak S. Gautam;Chris Botting;Nicholas Dohmeier;Fariborz Musavi;
Apparue dans: IEEE Transactions on Industry Applications
Date publication: 04.-2017, volume: 53, issue:2, pages: 1406 - 1415
Editeur: IEEE
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» A Jam-Absorption Driving Strategy for Mitigating Traffic Oscillations
Résumé:
To mitigate traffic oscillations that usually sustainably propagate upstream, this paper proposes a jam-absorption driving (JAD) strategy in the framework of Newell's car-following theory. The basic idea of the JAD strategy is to guide a vehicle to move slowly before being captured by an oscillation and terminate the slow movement when the vehicle would start to leave the jam if no such slow movement was implemented. To practically implement the idea, a two-step method is proposed to estimate the time–space ending point of the strategy, and a proper vehicle is selected to implement the JAD strategy based on a given expected absorbing speed and current traffic conditions. To test the JAD strategy, two simulated traffic scenarios are constructed based on a realistic data-driven car-following model. The first scenario, which only reproduces one oscillation, directly shows the effectiveness of the JAD idea in preventing wave propagation and capacity drop. The second scenario, which contains a series of traffic oscillations induced by the rubbernecking behavior, validates the proposed JAD strategy in more complicated and realistic conditions. It is indicated that the JAD strategy is able to absorb traffic oscillations; thus, the side effects incurred by the oscillations could be subsequently mitigated. The significance of this paper is to provide us a new idea to mitigate traffic oscillations, i.e., the JAD strategy.
Auteurs: Zhengbing He;Liang Zheng;Liying Song;Ning Zhu;
Apparue dans: IEEE Transactions on Intelligent Transportation Systems
Date publication: 04.-2017, volume: 18, issue:4, pages: 802 - 813
Editeur: IEEE
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» A Joint Vibration and Arcing Measurement System for Online Condition Monitoring of Onload Tap Changer of the Power Transformer
Résumé:
Vibration measurement has been adopted in some utilities in Australia, Canada, and several European countries for online condition monitoring of the power transformer's onload tap changer (OLTC). By comparing measured vibration signals at different stages, it might be possible to assess changes of OLTC's condition. However, there are still considerable difficulties in correlating vibration signals to the events of OLTC operation, which may impair the capability of vibration measurement for OLTC condition monitoring. Therefore, arcing measurement is proposed in this paper to complement the vibration measurement. Arcing is provoked when the OLTC switching contact closes at a fixed tap position and can lead to electromagnetic signals flowing through transformer windings, finally reaching earth. The arcing measurement is achieved by using a high-frequency current transducer (HFCT) clamping on the transformer's grounding cable. The joint vibration and arcing measurement can provide a better means for interpreting events involved in OLTC operation and facilitating improved OLTC condition monitoring. Since HFCT measured arcing signals can be coupled with noise, a probabilistic wavelet transform is thus employed in this paper to extract arcing signals from noise. Field measurements on two different types of OLTCs are performed using the joint vibration and arcing measurement system to validate the proposed methodology.
Auteurs: Junhyuck Seo;Hui Ma;Tapan Kumar Saha;
Apparue dans: IEEE Transactions on Power Delivery
Date publication: 04.-2017, volume: 32, issue:2, pages: 1031 - 1038
Editeur: IEEE
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» A Kernel Least Squares Based Approach for Nonlinear Quality-Related Fault Detection
Résumé:
In this paper, a nonlinear quality-related fault detection approach is proposed based on kernel least squares (KLS) model. The major novelty of the proposed method is that it utilizes KLS model to exploit the entire correlation between feature and output matrices. First, it uses a nonlinear projection function to map original process variables into feature space in which the correlation between feature and output matrices is realized by means of KLS. Then, the feature matrix is decomposed into two orthogonal parts by singular value decomposition and the statistics for each part are determined appropriately for the purpose of quality-related fault detection. Compared with existing kernel partial least squares (KPLS) based approaches, the proposed new method has the following obvious advantages. 1) It extracts the full correlation information of feature matrix, while KPLS-based approaches only use the partial correlation of several selected latent variables; therefore, it is more stable than the existing ones. 2) It omits the iterative computation of KPLS model and the determination of the number of latent variables; therefore, it is more efficient in engineering implementation. 3) It only uses two statistics to determine the type of fault, while most of the KPLS-based approaches need four; therefore, it has a more simple diagnosis logic. For simulation verification, a widely used literature example and an industrial benchmark are utilized to evaluate the performance of the proposed method.
Auteurs: Guang Wang;Jianfang Jiao;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 3195 - 3204
Editeur: IEEE
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» A Large Deviations Approach to Secure Lossy Compression
Résumé:
A Shannon cipher system for memoryless sources in which distortion is allowed at the legitimate decoder is considered. The source is compressed using a secured rate distortion code, which satisfies a constraint on the compression rate, as well as a constraint on the exponential rate of the excess-distortion probability at the legitimate decoder. Secrecy is measured by the exponential rate of the exiguous-distortion probability at the eavesdropper, rather than by the traditional measure of equivocation. The perfect-secrecy exponent is defined as the maximal exiguous-distortion exponent achievable when the key rate is unlimited. The reproduction-based estimate exponent is defined as the maximal exiguous-distortion exponent achievable for a genie-aided eavesdropper, which knows the secret key. Under limited key rate, it is proved that the maximal achievable exiguous-distortion exponent is equal to the minimum between the key rate plus the reproduction-based estimate exponent, and the perfect-secrecy exponent. The result is generalized to a fairly general class of variable key-rate and coding-rate codes.
Auteurs: Nir Weinberger;Neri Merhav;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 04.-2017, volume: 63, issue:4, pages: 2533 - 2559
Editeur: IEEE
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» A Line-Based-Clustering Approach for Ball Grid Array Component Inspection in Surface-Mount Technology
Résumé:
In production processes that use surface-mount technology (SMT) for the assembly of printed circuit boards, automated optical inspection is widely employed to diagnose component defects. However, commonly used inspection algorithms can hardly meet reliability and time efficiency requirements simultaneously, especially when applied to the components of high-density and large-scale integration, such as ball grid array (BGA). In this paper, a novel approach is presented to inspect BGA component defects. An adaptive thresholding combined with modified (ε, δ)-component segmentation is first performed to extract the grayscale image of solder balls. A line-based-clustering method is then proposed to recognize ball array. Simultaneously, accurate position and orientation of BGA are obtained based on the recognition results. Finally, ball features are extracted to diagnose potential defects. The proposed algorithm is implemented on the host computer of Samsung SMT 482 machine. The results obtained show that the proposed approach is suitable for a vast majority of BGAs with different ball arrays and also that it is robust to interferences caused by the image segmentation. Furthermore, compared to Samsung's algorithm, it has significant advantages in time efficiency and high inspection accuracy under nonideal lighting conditions.
Auteurs: Huijun Gao;Wanxin Jin;Xianqiang Yang;Okyay Kaynak;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 3030 - 3038
Editeur: IEEE
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» A Linear Bound on the Number of States in Optimal Convex Characters for Maximum Parsimony Distance
Résumé:
Given two phylogenetic trees on the same set of taxa $X$ , the maximum parsimony distance $d_mathrm{MP}$ is defined as the maximum, ranging over all characters $chi$ on $X$ , of the absolute difference in parsimony score induced by $chi$ on the two trees. In this note, we prove that for binary trees there exists a character achieving this maximum that is convex on one of the trees (i.e., the parsimony score induced on that tree is equal to the number of states in the character minus 1) and such that the number of states in the character is at most $7d_mathrm{MP}-5$ . This is the first non-trivial bound on the number of states required by optimal characters, convex or otherwise. The result potentially has algorithmic significance because, unlike general characters, convex characters with a bounded number of states can be enumerated in polynomial time.
Auteurs: Olivier Boes;Mareike Fischer;Steven Kelk;
Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Date publication: 04.-2017, volume: 14, issue:2, pages: 472 - 477
Editeur: IEEE
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» A Liquid Optical Phase Shifter With an Embedded Electrowetting Actuator
Résumé:
We demonstrate an electrowetting-based liquid optical phase shifter. The phase shifter consists of two immiscible liquid layers with different refractive indices. Sandwiched between the two liquids is a rigid membrane that moves freely along the optical axis and is supported by a compliant surround. When applied with a pressure, the thicknesses of both liquid layers change, which induces a difference in optical path, resulting in a phase shift. A miniaturized electrowetting-based actuator is used to produce hydraulic pressure. A multi-layered SU8 bonded structure was fabricated. A phase shift of 171° was observed when the device was incorporated in the Mach–Zehnder interferometer and driven with 100 V. [2016-0201]
Auteurs: Alireza Ousati Ashtiani;Hongrui Jiang;
Apparue dans: Journal of Microelectromechanical Systems
Date publication: 04.-2017, volume: 26, issue:2, pages: 305 - 307
Editeur: IEEE
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» A Low Complexity Diversity Achieving Decoder Based on a Two-Stage Lattice Reduction in Frequency-Selective MIMO Channels
Résumé:
Based on the V-BLAST zero-padded block transmission scheme in the frequency-selective multiple-input multiple-output channels, we propose a two-stage lattice-reduction (LR)-aided decoder and prove analytically that it can achieve the maximum diversity gain, which is equal to the product of the number of receive-antennas and the number of multipath channel taps. In the proposed decoding method, at first, we decouple the detection problem into several reduced-size detection problems and perform the lattice reduction algorithm for the decoupled blocks. Then, by choosing a proper threshold, a clustering algorithm divides the blocks into the maximum two clusters. We prove that the corresponding blocks of the first cluster achieve the full diversity through their linear equalization. For the remainder of the blocks, based on the entire observations of the second cluster, we propose an LR-aided detection method, which decodes the information symbols in this cluster with full diversity. Our proposed two-stage LR-aided algorithm performs better than the conventional LR-aided detection in terms of both the decoding computational complexity and the error probability. Additionally, we prove analytically that at high signal-to-noise ratio, the decoding complexity of the proposed decoder is equal to that of decoding the first cluster.
Auteurs: Mehrdad Niroomand;Mostafa Derakhtian;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 04.-2017, volume: 16, issue:4, pages: 2465 - 2477
Editeur: IEEE
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» A Low Energy-Noise 65nm CMOS Switched-Capacitor Resistive-Bridge Sensor Interface
Résumé:
A low energy-noise switched-capacitor (SC) sensor interface for resistive bridge sensor is presented. The SC amplifier achieves low-power metric with two operating modes using operation-phase-dependent biasing and compensation scheme in the op-amp design. This novel op-amp works in high-bandwidth high-power mode to sample the bridge signal for $13mu text {s}$ twice and in low-bandwidth low-power mode for $474mu text {s}$ over $500mu text {s}$ measurement interval. To further reduce the power of the SC amplifier in system level, a SC level-shift design is adopted. Regarding offset calibration, a capacitor divider based trimming scheme is implemented to generate the mid-point DC output voltage under the constraint of the feedback capacitor size. Implemented in 65 nm CMOS, the SC interface together with the regulator, voltage reference and trimming circuit occupies an area of 0.358 mm2. For the first test setup utilizing Half Wheatstone Bridge, the proposed SC amplifier consumes $12.3mu text {W}$ at 1 V regulated supply with a 2 kHz system clock. The measured Signal-to-Noise Ratio (SNR) of SC circuit is 55.6 dB. In the second test setup using a commercial sensor with 0.092 mV/kPa sensitivity, the interface has demonstrated the sensing function with sensitivity of 3.52 mV/kPa. Finally, compared to the representative prior-arts, this work has achieved the best energy-noise figure-of-merit at identical fractional resistance change.
Auteurs: K. C. Koay;P. K. Chan;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 04.-2017, volume: 64, issue:4, pages: 799 - 810
Editeur: IEEE
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» A Low-Complexity Policy for Outage Probability Minimization With an Energy Harvesting Transmitter
Résumé:
Outage probability in an energy harvesting (EH) block-fading communication system is studied in the finite-horizon online setting. First, the offline version of the problem is considered, and formulated as a mixed integer linear program (MILP). Then, the infinite-horizon online problem (IIL) is considered relaxing the battery constraints. Solutions of these two problems provide lower bounds on the finite-horizon online problem, for which we provide a low-complexity heuristic scheme, called the fixed threshold transmission (FTT) scheme. Numerical results show that the FTT scheme achieves an outage performance close to the MILP lower bound for a wide range of operation regimes, and close to IIL when the EH rate is low. It is also observed that the power allocated by the FTT scheme resembles the optimal offline solution with high probability, despite the lack of information about future channel states and energy arrivals.
Auteurs: Arif Onder Isikman;Melda Yuksel;Deniz Gündüz;
Apparue dans: IEEE Communications Letters
Date publication: 04.-2017, volume: 21, issue:4, pages: 917 - 920
Editeur: IEEE
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» A Low-Cost Laboratory-Based Polarimetric Synthetic Aperture Radar System for Scattering Analysis [Education Corner]
Résumé:
The scattering mechanisms captured using polarimetric synthetic aperture radar (PolSAR) imaging enable applications like target detection and image classification. This article presents PolSAR images from a unique low-cost, laboratory-based imaging system that captures the basic scattering mechanisms using radar calibration targets, such as a flat plate and dihedral and trihedral corner reflectors. The characterization of the basic scattering mechanisms with good ground truth information is important for classification with PolSAR imagery and for modeling polarimetric signatures. The PolSAR instrument is calibrated using a corner reflector, and the calibration is then validated using an independent data set. The calibration is done in terms of radar cross section (RCS) in decibels referenced to a square meter (dBsm). Results show the system is capable of capturing the basic scattering mechanisms of the single and double bounce. Validation results of the calibration process are off by about 3 dBsm and 4.5 dBsm from the theoretical values of the RCS for the vertical transmit-vertical receive (VV) and horizontal transmit-horizontal receive (HH) channel calibration, respectively. This is acceptable for a low-cost system capable of differentiating scattering mechanisms. This PolSAR system can be used for experimentation within the laboratory for phenomenology studies.
Auteurs: Sanjit Maitra;Michael G. Gartley;John P. Kerekes;
Apparue dans: IEEE Antennas and Propagation Magazine
Date publication: 04.-2017, volume: 59, issue:2, pages: 130 - 141
Editeur: IEEE
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» A Low-Dispersion Realization of a Rectangular Grid With PITD Method Through Artificial Anisotropy
Résumé:
Through using a nonuniform rectangular grid in the time-domain algorithm, the computational efficiency can be improved obviously, but the numerical anisotropic dispersion error is seriously deteriorative. In this letter, a rectangular grid with the precise-integration time-domain method through artificial anisotropy is proposed to reduce the numerical dispersion error of a rectangular grid. Both the stability condition and the numerical dispersion equation are obtained analytically, and the numerical anisotropic dispersion of the proposed method is examined in detail. It is found that the numerical dispersion error can be reduced obviously and can also be made nearly independent of the time-step size. The numerical experiments validate and verify that the proposed method is of higher accuracy and efficiency.
Auteurs: Zhen Kang;Xikui Ma;Jinghui Shao;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 04.-2017, volume: 27, issue:4, pages: 320 - 322
Editeur: IEEE
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» A Low-Loss Hybrid Bypass for DC Fault Protection of Modular Multilevel Converters
Résumé:
Without additional circuitry, the half-bridge modular multilevel converter (HB-MMC) is endangered under dc-side faults. Typically, a bypass thyristor is augmented to each HB cell to take up fault current until ac circuit breakers interrupt the dc fault. This paper proposes a dc fault protection concept for HB-MMC stations that requires insignificant extra silicon area relative to the thyristor bypass concept. Herein, bypass thyristors of typical HB cells are rearranged such that an independent modular shadow rectifier bridge (SRB) is formed. A low-loss switch assembly is utilized to immediately isolate the MMC following fault detection and the SRB suppresses the fault current by injecting a reverse dc voltage. Among several advantages, the proposed arrangement incurs insignificant losses in steady state, and in some arrangements the MMC is capable of operating in STATCOM mode briefly after fault inception to support ac grid voltage. The proposed concept may be suitable for clearing temporary faults on overhead HVdc lines. Several structural variations will be viewed and discussed. Applicability for a two-level voltage source converter will be addressed. The concept is validated by detailed numerical simulations of a ±200-kV HB-MMC station under dc fault.
Auteurs: I. A. Gowaid;
Apparue dans: IEEE Transactions on Power Delivery
Date publication: 04.-2017, volume: 32, issue:2, pages: 599 - 608
Editeur: IEEE
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» A Low-Power Microcontroller in a 40-nm CMOS Using Charge Recycling
Résumé:
A 40-nm microcontroller featuring voltage stacked memory and logic is presented. This involved connecting the power domains of the memory and logic in series, such that the ground of one power domain is connected to the positive supply rail of the other. In this paper, an ARM Cortex-M0+ and its peripherals are powered from 0 V to $V_{{mathrm{DD}}}$ , while its 4-kB ROM and the 16-kB SRAM are powered from $V_{{mathrm{DD}}}$ to 2 $V_{{mathrm{DD}}}$ . Since the memory and logic will, in general, draw different supply currents, the midrail $V_{{mathrm{DD}}}$ is provided by an on-chip switched capacitor voltage regulator (SCVR). To allow a direct comparison of voltage stacking with a conventional single supply, it can be turned off by configuring the SCVR to power both the memory and logic from 0 V and $V_{{mathrm{DD}}}$ . Turning on voltage stacking results in 96% power conversion efficiency, while the active converter area is reduced by 2.6 $times $ . Despite the use of a smaller SCVR, the voltage stacking reduces the supply noise by 3.4 dB and the output voltage drops from 58 to 36 mV.
Auteurs: Kristof Blutman;Ajay Kapoor;Arjun Majumdar;Jacinto Garcia Martinez;Juan Echeverri;Leo Sevat;Arnoud P. van der Wel;Hamed Fatemi;Kofi A. A. Makinwa;José Pineda de Gyvez;
Apparue dans: IEEE Journal of Solid-State Circuits
Date publication: 04.-2017, volume: 52, issue:4, pages: 950 - 960
Editeur: IEEE
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» A Low-Voltage SRAM Sense Amplifier With Offset Cancelling Using Digitized Multiple Body Biasing
Résumé:
With continued CMOS technology scaling down, transistors exhibit higher degrees of variation and mismatch, resulting in a larger offset voltage. A large offset voltage will enlarge bitline swing, increasing dynamic power consumption during a read operation and degrading the sensing decision correct rate and operation speed. Thus, the offset voltage is the most critical metric for static random access memory sense amplifiers (SAs), mainly arising from transistor threshold voltage mismatch. Here we propose an offset-cancelling technique with digitized multiple body biasing. In this scheme, SA transistor threshold voltage mismatch is compensated by adjusting the body bias voltage digitally and repeatedly. Simulation results in 130-nm CMOS technology show that the proposed calibration technique can reduce the standard deviation of the offset voltage by over four times comparing to a conventional SA, with about 6.5% and 1.6% area power overhead of a 6-kbit prototype chip introduced.
Auteurs: Bingyan Liu;Jiangzheng Cai;Jia Yuan;Yong Hei;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 442 - 446
Editeur: IEEE
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» A Maximum Likelihood Approach for SSS Detection in LTE Systems
Résumé:
Before establishing a communication link with the serving base station (eNodeB), user equipment (UE) operating in a long-term evolution (LTE) multi-cellular network must acquire some specific information, including the sector identity and cell group identity. For this purpose, two training sequences called primary synchronization signal (PSS) and secondary synchronization signal (SSS) are periodically transmitted in the downlink to convey such information. In this work, we present a novel maximum likelihood (ML) approach for SSS detection assuming that the PSS has been successfully identified at an earlier stage. As we shall see, the resulting scheme turns out to be too complex for practical implementation as it requires perfect knowledge of the channel covariance matrix. Therefore, we look for simpler solutions and propose two reduced-search methods that operate in a mismatched mode. The first scheme exploits channel state information emerging from both the primary and secondary synchronization signals, while the second scheme operates using only the secondary synchronization signal. Numerical analysis indicates that the proposed methods outperform existing alternatives and can be successfully applied even in a severe propagation scenario. The price for such an advantage is a certain increase of the processing requirement.
Auteurs: Michele Morelli;Marco Moretti;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 04.-2017, volume: 16, issue:4, pages: 2423 - 2433
Editeur: IEEE
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» A Meeting of Materials: Integrating Diverse Semiconductor Technologies for Improved Performance at Lower Cost
Résumé:
Using the DAHI approach and NGAS's DAHI foundry, we were able to successfully design and integrate three different semiconductor technologies (InP HBT, GaN HEMT, and Si CMOS) at the micron scale for enhanced RF performance. An InP HBT VCO and a GaN HEMT amplifier were integrated onto a common IBM 65-nm CMOS substrate to simultaneously achieve high efficiency, low phase noise, and high output power, with performance closely matched to design simulations. Spurred on by DARPA's DAHI challenge, Northrop Grumman has developed a working foundry capable of delivering heterogeneous integrated circuits to the microwave market.
Auteurs: Augusto Gutierrez-Aitken;Bryan Yi-Cheng Wu;Dennis Scott;Ken Sato;Benjamin Poust;Monte Watanabe;Cedric Monier;Nancy Lin;Xiang Zeng;Eric Nakamura;Peter Cheng;Eric Kaneshiro;Wesley Chan;Ioulia Smorchkova;Khanh Thai;Sujane Wang;David Slavin;Aaron Oki;Rey
Apparue dans: IEEE Microwave Magazine
Date publication: 04.-2017, volume: 18, issue:2, pages: 60 - 73
Editeur: IEEE
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» A MEMS Implementation of the Classic Meissner Parametric Resonator: Exploring High-Order Windows of Unbounded Response
Résumé:
In recent years, increasing attention is given to parametric resonators, in which an unbounded response may be induced by periodically modulating one of the system parameters. Parametric resonators with a single degree of freedom have many windows of unbounded response in which the response frequency is different from the modulation frequency. This difference between input and output frequencies may be relevant to sensing applications. In this paper, we explore the solution map of the Meissner parametric resonator, and we experimentally characterize odd-ordered windows of unbounded response, up to the 15th window. Another interesting feature of the Meissner resonator is discrete crossover points in which an unbounded response is possible at distinct modulation frequencies and distinct modulation amplitudes. In this paper, we experimentally characterize one such crossover point. Our parametric resonator is based on an electrostatic anti-spring, which allows to modulate stiffness that is otherwise unaffected by motion. This is in contrast to many previous experimental studies in which the modulated stiffness was affected by motion and thus included unwanted nonlinear effects. [2016-0209]
Auteurs: Shai Shmulevich;David Elata;
Apparue dans: Journal of Microelectromechanical Systems
Date publication: 04.-2017, volume: 26, issue:2, pages: 325 - 332
Editeur: IEEE
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» A Method of Calculating LC Parameters of Balancing Compensators for AC Arc Furnaces
Résumé:
A method of calculating LC parameters of a reactive balancing compensator for AC arc furnaces at the supply voltage asymmetry is the subject of this paper. The developed method is illustrated numerically with the calculation of LC parameters of a balancing compensator for an AC arc furnace approximated by a linear model with fixed parameters. The presented method can be regarded as an initial step toward developing balancing compensation for ultra-high-power AC arc furnaces. The method of calculation of LC parameters of balancing compensators is based in this paper on the Currents' Physical Component (CPC) power theory.
Auteurs: Leszek S. Czarnecki;Prashanna D. Bhattarai;
Apparue dans: IEEE Transactions on Power Delivery
Date publication: 04.-2017, volume: 32, issue:2, pages: 688 - 695
Editeur: IEEE
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» A Millimeter-Wave Gyroelectric Waveguide Isolator
Résumé:
In this paper, a new type of millimeter-wave waveguide isolator is demonstrated. After developing an analytical model for a rectangular waveguide loaded with stratified media, all the modes propagating through the structure are found. Isolators are then designed by utilizing the frequency ranges where high nonreciprocal attenuation is identified. Here, an isolator is designed to work within the Ka-band by loading a WR-28 waveguide with a transversely magnetized indium antimonide (InSb) slab cooled to 77 K. Measured performance shows more than 20-dB isolation with 1-dB insertion loss, which agrees with theoretical predictions. Moreover, the effects of changing the magnetic bias ( $B_{0}$ ) and adding dielectric layers above the InSb slab were analyzed theoretically and verified through measurement. Results prove the possibility of achieving high isolation using a weaker magnetic bias by topping the gyroelectric slab with dielectric layers. Nonreciprocal behavior was also demonstrated using an isolator working at 105 GHz, where simulated results show more than 33-dB isolation with 1.16-dB insertion loss. The results presented in this paper could pave the way toward the realization of nonreciprocal components working in the submillimeter-wave and terahertz frequency ranges, where the performance of the classical ferrite device deteriorates.
Auteurs: Ghassan N. Jawad;Christopher I. Duff;Robin Sloan;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 04.-2017, volume: 65, issue:4, pages: 1249 - 1256
Editeur: IEEE
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» A Missing Data Approach to Data-Driven Filtering and Control
Résumé:
In filtering, control, and other mathematical engineering areas, it is common to use a model-based approach, which splits the problem into two steps: 1) model identification and 2) model-based design. Despite its success, the model-based approach has the shortcoming that the design objective is not taken into account at the identification step, i.e., the model is not optimized for its intended use. This technical note proposes an approach for data-driven filtering and control that combines the identification and the model-based design into one joint problem. The signal of interest is modeled as a missing part of a trajectory of the data generating system. Subsequently, the missing data estimation problem is reformulated as a mosaic-Hankel structured matrix low-rank approximation/completion problem. A local optimization method, based on the variable projections principle, is then used for its numerical solution. The missing data estimation approach and the solution method proposed are illustrated on filtering and smoothing examples.
Auteurs: Ivan Markovsky;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 04.-2017, volume: 62, issue:4, pages: 1972 - 1978
Editeur: IEEE
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» A Mixed Finite Element Method to Solve the EEG Forward Problem
Résumé:
Finite element methods have been shown to achieve high accuracies in numerically solving the EEG forward problem and they enable the realistic modeling of complex geometries and important conductive features such as anisotropic conductivities. To date, most of the presented approaches rely on the same underlying formulation, the continuous Galerkin (CG)-FEM. In this article, a novel approach to solve the EEG forward problem based on a mixed finite element method (Mixed-FEM) is introduced. To obtain the Mixed-FEM formulation, the electric current is introduced as an additional unknown besides the electric potential. As a consequence of this derivation, the Mixed-FEM is, by construction, current preserving, in contrast to the CG-FEM. Consequently, a higher simulation accuracy can be achieved in certain scenarios, e.g., when the diameter of thin insulating structures, such as the skull, is in the range of the mesh resolution. A theoretical derivation of the Mixed-FEM approach for EEG forward simulations is presented, and the algorithms implemented for solving the resulting equation systems are described. Subsequently, first evaluations in both sphere and realistic head models are presented, and the results are compared to previously introduced CG-FEM approaches. Additional visualizations are shown to illustrate the current preserving property of the Mixed-FEM. Based on these results, it is concluded that the newly presented Mixed-FEM can at least complement and in some scenarios even outperform the established CG-FEM approaches, which motivates a further evaluation of the Mixed-FEM for applications in bioelectromagnetism.
Auteurs: J. Vorwerk;C. Engwer;S. Pursiainen;C. H. Wolters;
Apparue dans: IEEE Transactions on Medical Imaging
Date publication: 04.-2017, volume: 36, issue:4, pages: 930 - 941
Editeur: IEEE
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» A Mixed Reality Telepresence System for Collaborative Space Operation
Résumé:
This paper presents a mixed reality (MR) system that results from the integration of a telepresence system and an application to improve collaborative space exploration. The system combines free viewpoint video with immersive projection technology to support nonverbal communication (NVC), including eye gaze, interpersonal distance, and facial expression. Importantly, these features can be interpreted together as people move around the simulation, maintaining a natural social distance. The application is a simulation of Mars, within which the collaborators must come to agreement over; for example, where the Rover should land and go. The first contribution is the creation of an MR system supporting contextualization of NVC. Two technological contributions are prototyping a technique to subtract a person from a background that may contain physical objects and/or moving images and a lightweight texturing method for multiview rendering, which provides balance in terms of visual and temporal quality. A practical contribution is the demonstration of pragmatic approaches to sharing space between display systems of distinct levels of immersion. A research tool contribution is a system that allows comparison of conventional authored and video-based reconstructed avatars, within an environment that encourages exploration and social interaction. Aspects of system quality, including the communication of facial expression and end-to-end latency are reported.
Auteurs: Allen J. Fairchild;Simon P. Campion;Arturo S. García;Robin Wolff;Terrence Fernando;David J. Roberts;
Apparue dans: IEEE Transactions on Circuits and Systems for Video Technology
Date publication: 04.-2017, volume: 27, issue:4, pages: 814 - 827
Editeur: IEEE
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» A Mixed Transmission Strategy to Achieve Energy Balancing in Wireless Sensor Networks
Résumé:
In this paper, we investigate the problem of energy balanced data collection in wireless sensor networks, aiming to balance energy consumption among all sensor nodes during the data propagation process. Energy balanced data collection can potentially save energy consumption and prolong network lifetime, and hence, it has many practical implications for sensor network design and deployment. The traditional hop-by-hop transmission model allows a sensor node to propagate its packets in a hop-by-hop manner toward the sink, resulting in poor energy balancing for the entire network. To address the problem, we apply a slice-based energy model, and divide the problem into inter-slice and intra-slice energy balancing problems. We then propose a probability-based strategy named inter-slice mixed transmission protocol and an intra-slice forwarding technique to address each of the problems. We propose an energy-balanced transmission protocol by combining both techniques to achieve total energy balancing. In addition, we study the condition of switching between inter-slice transmission and intra-slice transmission, and the limitation of hops in an intra-slice transmission. Through our extensive simulation studies, we demonstrate that the proposed protocols achieve energy balancing, prolong network lifespan, and decrease network delay, compared with the hop-by-hop transmission and a cluster-based routing protocol under various parameter settings.
Auteurs: Tong Liu;Tao Gu;Ning Jin;Yanmin Zhu;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 04.-2017, volume: 16, issue:4, pages: 2111 - 2122
Editeur: IEEE
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» A Model for Single Neuron Activity With Refractory Effects and Spike Rate Estimation Techniques
Résumé:
The use of random point processes as models for neural spike trains allows the derivation of powerful statistical estimation techniques for time varying firing rates. Frequently, however, such estimators are based on the assumption that spike sequences follow a Poisson point process. Because of the bio-physical properties of neuronal action potentials, spike trains are affected by the refractory phenomenon that induces history dependency, and hence contradicts the Poisson assumption. In this work we present a neural spiking model, and a Maximum Likelihood (ML) estimation framework for time varying firing rates, that account for history dependencies in spike trains. Our framework is based on an exponential of polynomial model for the excitation function (stimulus), that generates a self exciting point process representing spike trains with absolute as well as relative refractory effects. Using this framework we employ techniques based on non-convex optimization and model order selection to derive ML estimators for neuronal firing rates. Results on simulated data with a refractory period show an improvement in accuracy when our estimation technique, that accounts for the complete refractory phenomenon, is used. Employing this estimation method for measured neuronal data shows an improvement in goodness of fit over estimators that do not account for the refractory effect, and also over other commonly used techniques.
Auteurs: Scott Monk;Harry Leib;
Apparue dans: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Date publication: 04.-2017, volume: 25, issue:4, pages: 306 - 322
Editeur: IEEE
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» A Motion-Sensorless Control for Intake Valves in Combustion Engines
Résumé:
This paper proposes a position observer and a velocity estimator of a nonlinear actuator for an application in a sensorless control system for engines. This is realized using a position observer and a velocity estimator combined in a cascade structure. The position observer is designed using a Lyapunov approach as typically done in the nonlinear observer approach. The velocity estimator is realized using the model of a proposed electromagnetic actuator. The Lyapunov-based observer estimates the valve position by using the coil current as an input signal and the estimated valve velocity as an output signal. The results are compared with an extended Kalman filter (EKF) used as an observer and developed for the same application. Moreover, the numerical complexity of the algorithm and the comparison with the developed EKF is also taken into account in the paper. The actuator is controlled using a discrete and analogous proportional derivative (PD) controller combined with a feedforward action to compensate for the stationer error. The final part of this paper contains validations of the proposed observed and controlled strategy by means of real measurements.
Auteurs: Paolo Mercorelli;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 04.-2017, volume: 64, issue:4, pages: 3402 - 3412
Editeur: IEEE
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» A Multi-Timescale and Bilevel Coordination Approach for Matching Uncertain Wind Supply With EV Charging Demand
Résumé:
The matching between random wind supply and electric vehicle (EV) charging demand can reduce the requirement of traditional power sources and the emission of CO2. This problem is of great practical interest but involves system dynamics in multiple timescales. We consider this an important problem in this paper. In order to capture the randomness in the wind supply and EV charging demand, we formulate the problem as a bilevel Markov decision process. At the upper level, the charging demand of EVs in different locations is aggregated into multiple aggregators. The system operator dispatches power among the aggregators in a coarse timescale to maximize the wind power utilization. At the lower level, the aggregator schedules the charging process of individual EVs at a finer timescale to minimize the charging cost. In order to solve this large-scale problem, a bilevel simulation-based policy improvement (SBPI) method is developed. It is mathematically proved that the SBPI can improve from base policies in both levels. The performance of this multi-timescale and bilevel coordination approach is demonstrated through case studies in the city of Beijing.
Auteurs: Qilong Huang;Qing-Shan Jia;Xiaohong Guan;
Apparue dans: IEEE Transactions on Automation Science and Engineering
Date publication: 04.-2017, volume: 14, issue:2, pages: 694 - 704
Editeur: IEEE
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» A Multiagent Minority-Game-Based Demand-Response Management of Smart Buildings Toward Peak Load Reduction
Résumé:
This paper presents a cyber-physical management of smart buildings based on smart-gateway network with distributed and real-time energy data collection and analytics. We consider a building with multiple rooms supplied with one main electricity grid and one additional solar energy grid. Based on smart-gateway network, energy signatures of rooms are first extracted with consideration of uncertainty and further classified as different types of agents. Then, a multiagent minority-game (MG)-based demand-response management is introduced to reduce peak demand on the main electricity grid and also to fairly allocate solar energy on the additional grid. Experiment results show that compared to the traditional static and centralized energy-management system (EMS), and the recent multiagent EMS using price-demand competition, the proposed uncertainty-aware MG-EMS can achieve up to 50\times and 145\times utilization rate improvements, respectively, regarding to the fairness of solar energy resource allocation. More importantly, the peak load from the main electricity grid is reduced by 38.50% in summer and 15.83% in winter based on benchmarked energy data of building. Lastly, an average 23% uncertainty can be reduced with an according 37% balanced energy allocation improved comparing to the MG-EMS without consideration of uncertainty.
Auteurs: Hantao Huang;Yuehua Cai;Hang Xu;Hao Yu;
Apparue dans: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Date publication: 04.-2017, volume: 36, issue:4, pages: 573 - 585
Editeur: IEEE
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» A Multiobjective Cooptimization of Buffer and Wire Sizes in High-Performance Clock Trees
Résumé:
Clock buffer and wire sizing are intertwined problems that also greatly impact power consumption and skew in clock trees. Due to their complexity, they are often solved separately, leading to suboptimal solutions. In this brief, we propose a new formulation for cooptimization of buffer and wire sizes for high-performance clock trees. Using the proposed cooptimization of buffer and wire sizes, we are able to minimize a combination of both power and skew. The variation-aware experiments show that, by applying the proposed formulation, power and skew for all tested clock trees are improved. On average, we achieve a reduction of 57% in power and 50 ps in skew. We also show that our solutions are Pareto optimal where power and skew cannot be further reduced simultaneously and they provide a balanced tradeoff between power and skew.
Auteurs: Amin Farshidi;Laleh Behjat;Logan Rakai;David Westwick;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 04.-2017, volume: 64, issue:4, pages: 412 - 416
Editeur: IEEE
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» A Multistep Dynamic Equivalent Method for Urban Power Grid Based on District Dividing
Résumé:
With the increasing demand of electricity, the development of the urban power grid has drawn a lot of attention in China. In order to focus on the analysis of an urban power grid, the remaining part of the large-scale power grid used is to be reduced. The accuracy of the equivalence is key to urban power grid research. In this paper, a multistep dynamic equivalent method based on district dividing is proposed. Based on the electrical distance, voltage level, and geographic location, the external system is divided into outer layer, inner layer, and buffer subsystem. Each district is separately reduced by different methods. The proposed technique is illustrated by a real large-scale power grid in the south of China.
Auteurs: Xiaoyan Yu;Ke-Jun Li;Mingqiang Wang;Zhuo-di Wang;Kaiqi Sun;Jie Lou;
Apparue dans: IEEE Transactions on Industry Applications
Date publication: 04.-2017, volume: 53, issue:2, pages: 908 - 917
Editeur: IEEE
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» A Multitask Diffusion Strategy With Optimized Inter-cluster Cooperation
Résumé:
We consider a multitask estimation problem where nodes in a network are divided into several connected clusters, with each cluster performing a least-mean-squares estimation of a different random parameter vector. Inspired by the adapt-then-combine diffusion strategy, we propose a multitask diffusion strategy whose mean stability can be ensured whenever individual nodes are stable in the mean, regardless of the inter-cluster cooperation weights. In addition, the proposed strategy is able to achieve an asymptotically unbiased estimation when the parameters have same mean. We also develop an inter-cluster cooperation weights selection scheme that allows each node in the network to locally optimize its inter-cluster cooperation weights. Numerical results demonstrate that our approach leads to a lower average steady-state network mean-square deviation, compared with using weights selected by various other commonly adopted methods in the literature.
Auteurs: Yuan Wang;Wee Peng Tay;Wuhua Hu;
Apparue dans: IEEE Journal of Selected Topics in Signal Processing
Date publication: 04.-2017, volume: 11, issue:3, pages: 504 - 517
Editeur: IEEE
Document complet vers site de l'éditeur
 


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