Electrical and Electronics Engineering publications abstract of: 03-2016 sorted by title, page: 0

» >70% Power-Added-Efficiency Dual-Gate, Cascode GaN HEMTs Without Harmonic Tuning
Abstract:
We report the state-of-the-art performance of deep-submicrometer gate length dual-gate GaN HEMTs and cascode GaN HEMTs with reduced gate-to-drain feedback capacitance compared with single-gate GaN HEMTs. With 150-nm gate length field-plated gate structures, these GaN HEMTs demonstrated improvement of small-signal gain by 10 dB, compared with single-gate GaN HEMTs. Large-signal load-pull measurements showed peak power-added-efficiency (PAE) of 71%–74% without harmonic tuning at 10 GHz, up to a measured continuous-wave output power level of 2.3–2.5 W. The 74% PAE is very close to a theoretical maximum PAE of 78.5% without harmonic tuning. Compared with single-gate GaN HEMTs, both the dual-gate and cascode GaN HEMTs offer % improvement in peak PAE at the output power of 2.3–2.5 W.
Autors: Moon, Jeong-Sun;Grabar, R.;Brown, D.;Alvarado-Rodriguez, I.;Wong, D.;Schmitz, A.;Fung, H.;Chen, P.;Kang, Jong-chan;Kim, S.;Oh, T.;McGuire, C.;
Appeared in: IEEE Electron Device Letters
Publication date: Mar 2016, volume: 37, issue:3, pages: 272 - 275
Publisher: IEEE
 
» “I Can’t Get No Satisfaction”: Helping Autonomous Systems Identify Their Unsatisfied Interdomain Interests
Abstract:
Given the distributed and business-driven nature of the Internet, economic interests of autonomous systems (ASes) may be incompatible. Previous works studied specific effects of incompatible interests, especially BGP policy conflicts leading to routing and forwarding anomalies. In this paper, we focus on the effects of incompatible interests that do not trigger such anomalies. We take the perspective of a single AS: we show that incompatible interests can have a tangible impact on its business and provide a classification of its unsatisfied interests. Since incompatible interests cannot be solved automatically, our effort is directed to support network managers in their business decisions. Hence, we describe algorithms to identify and assess their impact, as well as a prototype of a warning system aimed at signaling the most relevant unsatisfied interests. We evaluate our prototype on real data from two operational networks. In addition, to illustrate the potential of our system, our evaluation shows that unsatisfied interest are relatively frequent and likely affect a significant amount of traffic in practice.
Autors: Cardona, J.C.;Vissicchio, S.;Lucente, P.;Francois, P.;
Appeared in: IEEE Transactions on Network and Service Management
Publication date: Mar 2016, volume: 13, issue:1, pages: 43 - 57
Publisher: IEEE
 
» 1-D Lamination Models for Calculating the Magnetization Dynamics in Non-Oriented Soft Magnetic Steel Sheets
Abstract:
This paper presents 1-D dynamic magnetization models of non-oriented soft magnetic steel sheets that can be expressed as simple systems of ordinary differential equations. The discussed models take into account the dynamic effects on magnetization due to eddy currents and hysteresis inside such sheets and differ in the way the coupled Maxwell equations with hysteresis are solved. The presented modeling approaches include finite-difference schemes of different accuracies, various magnetic equivalent circuits (MECs), including a recent approach to eliminate the deficiencies of classical MECs, and a mesh-free approach. The different modeling approaches are analyzed and compared in terms of mathematical structure, implementation work, spatial discretization, and accuracy, where both voltage- and current-driven versions are investigated.
Autors: Petrun, M.;Steentjes, S.;Hameyer, K.;Dolinar, D.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 101 Online: American Minitel Network and Lessons from Its Failure
Abstract:
In 1981, videotex and virtual circuits were the hot computer network technologies and promised to bring the world to the masses. Amid a worldwide battle over standards, France started Minitel, which quickly became the first successful mass-market digital information-distribution ecosystem. In 1991, France Telecom launched the American version of Minitel, 101 Online, in San Francisco. 101 Online was as massive a failure as Minitel had been a success. This article reveals the previously undocumented history of the 101 Online ecosystem, suggests reasons why it failed where Minitel had succeeded, and draws lessons for the current policy debate on what information-network architecture and implementation best fosters digital innovation.
Autors: Mailland, J.;
Appeared in: IEEE Annals of the History of Computing
Publication date: Mar 2016, volume: 38, issue:1, pages: 6 - 22
Publisher: IEEE
 
» 2-D Analytical Modeling of Threshold Voltage for Graded-Channel Dual-Material Double-Gate MOSFETs
Abstract:
A 2-D analytical model for the surface potential and threshold voltage of graded-channel dual-material double-gate (GCDMDG) MOSFETs obtained by intermixing the concepts of graded doping in channel and dual material in gate engineering has been proposed. The parabolic approximation method has been explored for determining the potential distribution function of the device by solving Poisson’s equation with suitable boundary conditions. The threshold voltage roll-off, drain-induced barrier lowering and lateral electric field have also been examined. The effects of different device parameters on device performance have been evaluated to check its figure-of-merit over the graded-channel double-gate (GCDG) and dual-material double-gate (DMDG) structures. For validation of the proposed model, the results have been compared with the numerical simulation data obtained by ATLAS™, a 2-D device simulator from SILVACO.
Autors: Goel, E.;Kumar, S.;Singh, K.;Singh, B.;Kumar, M.;Jit, S.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2016, volume: 63, issue:3, pages: 966 - 973
Publisher: IEEE
 
» 2-D Reduced Model for Eddy Currents Calculation in Litz Wire and Its Application for Switched Reluctance Machine
Abstract:
The strong correlation between the level of eddy current losses and the winding geometry shows the necessity to pay attention to the manner of disposition of coils in machine slots. The conductor type, whether it is solid or stranded, also has a crucial influence. This paper suggests an electromagnetic analysis of complex stranded conductors, such as litz wire (LW) and twisted wire. Each conductor is composed of individual strands that are woven or twisted in the slot throughout the machine length. Combined with several electric circuit relationships that interpret the strands transposition, a 2-D finite-element (FE) model is developed in this paper so that the copper losses in each strand can be calculated individually. A model reduction is also proposed in the case of LWs. This allows the benefit of only one complete FE solution to find fast solutions in the slots’ domains when any variation of geometrical data occurrs. It allows adapting non-conforming subdomains’ meshes and seeing that it prevents the Newton–Raphson iterations and the moving band technique, the model reduction presents clear interests in repetitive analysis, such as winding optimization processes.
Autors: Al Eit, M.;Bouillault, F.;Marchand, C.;Krebs, G.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 3-D Electromagnetic Field Analysis Combined With Mechanical Stress Analysis for Interior Permanent Magnet Synchronous Motors
Abstract:
The method of 3-D electromagnetic field analysis combined with mechanical stress analysis has been developed for loss calculation of interior permanent magnet motors. Both the stator compressive stress caused by shrink fitting and the rotor tensile stress caused by centrifugal force are considered in the stress analysis. The 3-D flux density vector is calculated by the electromagnetic field analysis, including the core end regions. The variation in the stress effect with the angle between stress and flux vectors is considered using the equivalent stress. The calculated loss is compared with the experimental loss in order to confirm the validity of the analysis. It is clarified that the accuracy of loss calculation is significantly improved as compared with the conventional method that neglects the angles between the stress and flux density vector.
Autors: Yamazaki, K.;Aoki, A.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 3-D FE Method Analysis of Static Fields for Non-Conforming Meshes With Second-Order Node-Based Elements
Abstract:
A novel approach of using node-based, second-order polynomial shape functions to substitute the degrees of freedom corresponding to slave nodes by a linear combination of those corresponding to master nodes is shown to be a powerful and accurate tool to couple non-conforming meshes. This method is investigated and proposed to be used to consider moving domains, especially rotating parts. The numerical behavior is illustrated by an exhaustive accuracy investigation.
Autors: Wallinger, G.J.;Biro, O.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 3-D Microlens Phosphor With Curvatures Manufactured by Imprinting for Chip-on-Board Light-Emitting Diodes
Abstract:
High-power light-emitting diodes (LEDs) assembled in 3-D microlens-phosphor structures are investigated. For the proposed design, the phosphor–air interface with arrayed high-valued curvatures replaces the conventional flat counterpart, enabling abundant randomized lights to exit. Monte Carlo algorithm ray tracing and finite-element method were utilized in this paper to analyze the light propagation and thermal migration, simulatively indicating that the redirecting regulation and heat dispassion way of the proposed architecture are considerably different. Experimentally, in comparison with the conventional flat chip-on-board (COB) LEDs, the proposed single-layered structure is capable of improving the luminous efficacy of radiation by 38.1%. For multilayered structures, within which the light transmits first through red phosphor layer and then yellow phosphor layer molded with microlens, a 7% increase in quantum efficiency and an 8.7 increase in color rendering index have been achieved. The proposed structure can guide LED manufacturing communities to significantly improve the optical performance and designs of COB packaging.
Autors: Xiao, H.;Shih, T.-M.;Guo, Z.-Q.;Lin, Y.;Lu, Y.-J.;Chen, Z.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2016, volume: 63, issue:3, pages: 1128 - 1133
Publisher: IEEE
 
» 3-D Modeling of Heterogeneous and Anisotropic Superconducting Media
Abstract:
In this paper, we investigate the 3-D computation of the current distribution in the heterogeneous superconducting media with a discontinuous anisotropic – constitutive power law. The resulting 3-D vectorial non-linear diffusion problem satisfied by the electric field is solved in each region of the media with a discontinuous Galerkin method combined with a 3-D semi-implicit scheme recently proposed for the 3-D modeling of homogeneous bulk superconductors. Numerical applications on the media consisting of two embedded anisotropic superconducting regions with and without a conductive matrix are computed. Both critical current density and power law exponent are uniform in each region but discontinuous in the media. The results will show the continuity of the diffusion phenomena in the media and the differences between both isotropic and anisotropic cases under an applied axial sinusoidal magnetic field.
Autors: Makong, L.;Kameni, A.;Masson, P.;Lambrechts, J.;Bouillault, F.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 3-D Percolative Model-Based Multiscale Simulation of Randomly Aligned Networks of Carbon Nanotubes
Abstract:
A carbon nanotube (CNT) network is an aggregate of nanotubes with different properties, which is randomly deposited over a certain substrate. The way the CNTs are physically arranged gives the electrical behavior of the film that can be described by the percolation theory. However, due to the statistical nature of the problem, many aspects about the transport are still unknown. Here, we present a model based on a stochastic algorithm that can generate nonrigid solid objects in a 3-D space, emulating the typical fabrication processes involved with high fidelity. The properties of the nanotubes are extracted according to some probability distributions inferred from experimental measurements. The transport mechanisms are modeled according to the theory of 1-D ballistic channels based on the computation of the density-of-states. The behavior of the entire network is then simulated by coupling a SPICE program with an iterative algorithm that self-consistently calculates the electrostatic potential and the current flow in each node of the network. We performed several simulations of the conductivity of different networks and validated the model with experimental measurements. Our results suggest that the observed spread of the results between nominally identical networks is due to border effects, which are more pronounced in films close to their percolation threshold. We, furthermore, performed a study on the percolation threshold of different networks, finding good agreement with previous studies on the percolation theory.
Autors: Colasanti, S.;Bhatt, V.D.;Abdelhalim, A.;Lugli, P.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2016, volume: 63, issue:3, pages: 1346 - 1351
Publisher: IEEE
 
» 3.3-kV-Class 4H-SiC MeV-Implanted UMOSFET With Reduced Gate Oxide Field
Abstract:
A critical issue for SiC trench gate metal–oxide–semiconductor field-effect transistors (UMOSFETs) is gate oxide shielding from the electric field at the trench bottom. In this letter, low ON-resistance with low gate electric field was achieved in a 3.3-kV-class UMOSFET with a unique hexagonal buried p-base region formed by MeV ion implantation. The shielding effect was further enhanced by a self-aligned trench bottom shielding region. The specific ON-resistance, with and without the trench bottom shielding region, was 8.3 and 9.4 , respectively. The blocking voltage in each case was V. The electric field in the gate oxide with the trench bottom shielding region was reduced to 2.5 MV/cm at 3300 V.
Autors: Harada, S.;Kobayashi, Y.;Ariyoshi, K.;Kojima, T.;Senzaki, J.;Tanaka, Y.;Okumura, H.;
Appeared in: IEEE Electron Device Letters
Publication date: Mar 2016, volume: 37, issue:3, pages: 314 - 316
Publisher: IEEE
 
» 4H-SiC n-Channel Insulated Gate Bipolar Transistors on (0001) and (000-1) Oriented Free-Standing n Substrates
Abstract:
We experimentally demonstrate 4H-SiC n-channel, planar gate insulated gate bipolar transistors (IGBTs) on 180- thick lightly doped free-standing n substrates with ion-implanted collector regions, and metal–oxide–semiconductor gates on (0001) and (000-1) surfaces. The IGBTs show an ON-state current density of 20 A/cm2 at a power dissipation of 300 W/cm2. The threshold voltages are measured to be 7.5 V and 10.5 V on Si-face and C-face, respectively. Both IGBTs show a small positive temperature coefficient of the forward voltage drop, which is useful for easy parallelization of devices.
Autors: Chowdhury, S.;Hitchcock, C.;Stum, Z.;Dahal, R.;Bhat, I.B.;Chow, T.P.;
Appeared in: IEEE Electron Device Letters
Publication date: Mar 2016, volume: 37, issue:3, pages: 317 - 320
Publisher: IEEE
 
» 5G-Enabled Tactile Internet
Abstract:
The long-term ambition of the Tactile Internet is to enable a democratization of skill, and how it is being delivered globally. An integral part of this is to be able to transmit touch in perceived real-time, which is enabled by suitable robotics and haptics equipment at the edges, along with an unprecedented communications network. The fifth generation (5G) mobile communications systems will underpin this emerging Internet at the wireless edge. This paper presents the most important technology concepts, which lay at the intersection of the larger Tactile Internet and the emerging 5G systems. The paper outlines the key technical requirements and architectural approaches for the Tactile Internet, pertaining to wireless access protocols, radio resource management aspects, next generation core networking capabilities, edge-cloud, and edge-AI capabilities. The paper also highlights the economic impact of the Tactile Internet as well as a major shift in business models for the traditional telecommunications ecosystem.
Autors: Simsek, M.;Aijaz, A.;Dohler, M.;Sachs, J.;Fettweis, G.;
Appeared in: IEEE Journal on Selected Areas in Communications
Publication date: Mar 2016, volume: 34, issue:3, pages: 460 - 473
Publisher: IEEE
 
» 60 GHz Indoor Propagation With Time-Domain Geometric-Optics
Abstract:
60 GHz is one of the potential candidates in frequency spectrum for high-speed wireless communication. Geometrical optics in frequency domain (FDGO) is suffered from relative low accuracy and time consumption for frequency sweeping. In this paper, 60 GHz indoor propagation is studied with the time-domain geometric-optics (TDGO) method. The influence of slab walls with layered structures is considered. The accuracy of TDGO is validated by finite difference time domain. The result is compared with the results of FDGO and experiment in references.
Autors: Lyu, P.;Xu, X.;Yan, S.;Ren, Z.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» 64-APSK Constellation and Mapping Optimization for Satellite Broadcasting Using Genetic Algorithms
Abstract:
DVB-S2 and DVB-SH satellite broadcasting standards currently deploy 16- and 32-amplitude phase shift keying (APSK) modulation using the consultative committee for space data systems (CCSDS) mapping. Such standards also include hierarchical modulation as a mean to provide unequal error protection in highly variable channels over satellite. Foreseeing the increasing need for higher data rates, this paper tackles the optimization of 64-APSK constellations to minimize the mean square error between the original and received symbol. Optimization is performed according to the sensitivity of the data to the channel errors, by means of genetic algorithms, a well-known technique currently used in a variety of application domains, when close form solutions are impractical. Test results show that through non-uniform constellation and asymmetric symbol mapping, it is possible to significantly reduce the distortion while preserving bandwidth efficiency. Tests performed on real signals based on perceptual quality measurements allow validating the proposed scheme against conventional 64-APSK constellations and CCSDS mapping.
Autors: Anedda, M.;Meloni, A.;Murroni, M.;
Appeared in: IEEE Transactions on Broadcasting
Publication date: Mar 2016, volume: 62, issue:1, pages: 1 - 9
Publisher: IEEE
 
» 8K Terrestrial Transmission Field Tests Using Dual-Polarized MIMO and Higher-Order Modulation OFDM
Abstract:
Japan Broadcasting Corporation (NHK) is conducting research on the next-generation of digital terrestrial broadcasting that will enable ultrahigh definition television such as 8K. Multiple-input multiple-output (MIMO) technology should be able to expand the single-input single-output channel capacity. MIMO is adopted in ATSC3.0 as an optional method. In order to construct a next-generation terrestrial network using MIMO technology and to ensure an adequate link budget especially as regards the MIMO propagation parameters, two experimental stations have been installed in Hitoyoshi city, Kumamoto, Japan. This system is an extension of the conventional DTV system in Japan, called ISDB-T. NHK conducted MIMO field tests using one station and MIMO field tests using two stations composing a single frequency network (SFN). For the MIMO test, an advanced SFN using space time coding was developed. The MIMO field tests involved terrestrial 8K transmissions (91 Mb/s) over a single UHF band channel (6 MHz bandwidth). The degradation of required carrier to noise ratio compared to laboratory measurements in dual-polarized MIMO propagation was under 3 dB even in non-line-of-sight conditions. The MIMO field tests indicated that the required received power of the SFN was up to 3 dB better than that of the conventional SFN.
Autors: Saito, S.;Shitomi, T.;Asakura, S.;Satou, A.;Okano, M.;Murayama, K.;Tsuchida, K.;
Appeared in: IEEE Transactions on Broadcasting
Publication date: Mar 2016, volume: 62, issue:1, pages: 306 - 315
Publisher: IEEE
 
» – Volume Integral Formulations for Solving Electromagnetic Problems in the Frequency Domain
Abstract:
A volume integral formulation for solving electromagnetic problems in the frequency domain is proposed. First, it is based on a magnetic flux and current density face element interpolation for representing the electromagnetic problem through an equivalent circuit. Second, magnetic vector potentials A and electric vector potential T are considered, thanks to the use of finite element mesh connectivity matrices. The formulation is particularly well adapted to solving electromagnetic problems with large air domains, in the presence of thin electric regions and magnetic materials.
Autors: Meunier, G.;Chadebec, O.;Guichon, J.;Le-Van, V.;Siau, J.;Bannwarth, B.;Sirois, F.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» Adaptive Control for a Class of Uncertain Nonaffine-in-Control Nonlinear Systems
Abstract:
This technical note presents an adaptive controller for a class of nonlinear uncertain systems, nonaffine in control. As compared to previous architectures for nonlinear nonaffine-in-control systems, the solution discussed in this technical note admits a broader class of nonlinear systems by relaxing some of the (restrictive) assumptions previously made. We also consider a more general filtering structure and prove the results using partial knowledge of the control input actuator model. With the presented control architecture we are able to improve the performance and robustness of the closed-loop adaptive system, compared to prior results of adaptive control for nonaffine-in-control systems.
Autors: Choe, R.;Xargay, E.;Hovakimyan, N.;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Mar 2016, volume: 61, issue:3, pages: 840 - 846
Publisher: IEEE
 
» – Volume Integral Formulations for Solving Electromagnetic Problems in the Frequency Domain
Abstract:
A volume integral formulation for solving electromagnetic problems in the frequency domain is proposed. First, it is based on a magnetic flux and current density face element interpolation for representing the electromagnetic problem through an equivalent circuit. Second, magnetic vector potentials and electric vector potential are considered, thanks to the use of finite element mesh connectivity matrices. The formulation is particularly well adapted to solving electromagnetic problems with large air domains, in the presence of thin electric regions and magnetic materials.
Autors: Meunier, G.;Chadebec, O.;Guichon, J.;Le-Van, V.;Siau, J.;Bannwarth, B.;Sirois, F.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» Adaptive Control for a Class of Uncertain Nonaffine-in-Control Nonlinear Systems
Abstract:
This technical note presents an adaptive controller for a class of nonlinear uncertain systems, nonaffine in control. As compared to previous architectures for nonlinear nonaffine-in-control systems, the solution discussed in this technical note admits a broader class of nonlinear systems by relaxing some of the (restrictive) assumptions previously made. We also consider a more general filtering structure and prove the results using partial knowledge of the control input actuator model. With the presented control architecture we are able to improve the performance and robustness of the closed-loop adaptive system, compared to prior results of adaptive control for nonaffine-in-control systems.
Autors: Choe, R.;Xargay, E.;Hovakimyan, N.;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Mar 2016, volume: 61, issue:3, pages: 840 - 846
Publisher: IEEE
 
» q-Ary Chain-Containing Quantum Synchronizable Codes
Abstract:
We propose a general design of quantum synchronizable codes from classical -ary cyclic codes. With the aid of classical super/subcodes, the proposed method exploits the idea of chain-containing -ary cyclic codes when designing quantum synchronizable codes. The distance bound of the resulting quantum synchronizable codes of Calderbank-Shor-Steane (CSS) structure is derived using the representation of Mattson–Solomon polynomial.
Autors: Xie, Y.;Yang, L.;Yuan, J.;
Appeared in: IEEE Communications Letters
Publication date: Mar 2016, volume: 20, issue:3, pages: 414 - 417
Publisher: IEEE
 
» A 0.4-mW, 4.7-ps Resolution Single-Loop TDC Using a Half-Delay Time Integrator
Abstract:
A compact, low-power, single-loop third-order delta–sigma () time-to-digital converter (TDC) for time-mode signal processing is presented in this brief. In general, a high-resolution TDC requires a cascadable time integrator to increase the order of the loop filter. However, implementing the time integrator has been very challenging owing to the difficulty in storing time information. In this brief, we present a low-power half-delay time integrator, which is simply composed of two AND gates, a charge pump, and a comparator. The proposed time integrator can be easily cascaded (serially connected) to implement a loop filter with high-order noise shaping. The prototype TDC fabricated in 0.11- CMOS process occupies an active area of 0.11 mm, consuming 0.4 mW from a 1.2 V supply. It achieves the dynamic range of 81 dB over a signal bandwidth of 50 kHz, and the resolution of 4.7 ps over a measurable range of 39.06 ns, which is half the clock period.
Autors: Kwon, C.-K.;Kim, H.;Park, J.;Kim, S.-W.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2016, volume: 24, issue:3, pages: 1184 - 1188
Publisher: IEEE
 
» A 0.5 V, 14.28-kframes/s, 96.7-dB Smart Image Sensor With Array-Level Image Signal Processing for IoT Applications
Abstract:
This paper presents a smart image sensor with multiple operation modes, including edge extraction, multipoint tracking (MPT), and high-dynamic-range (HDR) imaging for wireless sensor nodes in Internet-of-Things applications. The pixel consists of a 0.5 V operated pulsewidth-modulation sensor for achieving HDR response and low fixed pattern noise. Array-level image signal processing is implemented using a local interpixel feedback network, in-pixel low power dynamic logics, and a corresponding peripheral with an event-driven hand-shaking readout. A prototype chip with a CMOS image sensor (CIS) array is designed and fabricated in a TSMC 0.18- CIS technology. In the MPT mode, the measured tracking speed is 14.28 kframes/s with an error of 0.36 pixels and a tracking capability up to four points. In the HDR imaging mode, the achieved DR is 96.7 dB.
Autors: Yin, C.;Chiu, C.-F.;Hsieh, C.-C.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2016, volume: 63, issue:3, pages: 1134 - 1140
Publisher: IEEE
 
» A 0.56–2.92 GHz Wideband and Low Phase Noise Quadrature LO-Generator Using a Single LC-VCO for 2G–4G Multistandard Cellular Transceivers
Abstract:
A wideband and low phase noise quadrature local oscillation (LO) signal generator for multistandard cellular transceivers was proposed. Using the new LO-plan consisting of divide-by-6, divide-by-4, and divide-by-12 frequency dividers, the required frequency-tuning range (FTR) of a voltage-controlled oscillator (VCO) was reduced to 39%, which can be easily covered by a single LC-VCO. Due to the reduced FTR, the VCO can retain a high Q-factor and achieve low phase noise. The key building block of the new LO-plan is a quadrature divide-by-6 divider, capable of generating precise I/Q signals. To implement the quadrature divide-by-6 divider, we proposed a fully differential divide-by-3 divider with 50% duty cycle. Using the same idea, a fully differential divide-by-2 circuit was also proposed for divide-by-4 and divide-by-12 dividers. The proposed LO-generator was fabricated in a 40 nm CMOS process, and covered LO-frequencies of 0.56–2.92 GHz for multistandard cellular transceivers. The LO-generator occupied a small silicon area of and achieved an excellent phase noise performance of at a 1 MHz offset from a 709 MHz LO-frequency.
Autors: Yoon, H.;Lee, Y.;Lim, Y.;Tak, G.-Y.;Kim, H.-T.;Ho, Y.-C.;Choi, J.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 614 - 625
Publisher: IEEE
 
» A 1.5 nW, 32.768 kHz XTAL Oscillator Operational From a 0.3 V Supply
Abstract:
This paper presents an ultra-low power crystal (XTAL) oscillator circuit for generating a 32.768 kHz clock source for real-time clock generation. An inverting amplifier operational from 0.3 V oscillates the XTAL resonator and achieves a power consumption of 2.1 nW. A duty-cycling technique powers down the XTAL amplifier without losing the oscillation and reduces the power consumption to 1.5 nW. The proposed circuit is implemented in 130 nm CMOS with an area of and achieves a temperature stability of 1.85 ppm/°C.
Autors: Shrivastava, A.;Akella Kamakshi, D.;Calhoun, B.H.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 686 - 696
Publisher: IEEE
 
» A 10 Gb/s Hybrid ADC-Based Receiver With Embedded Analog and Per-Symbol Dynamically Enabled Digital Equalization
Abstract:
While analog-to-digital converter (ADC)-based serial link receivers enable powerful digital equalization for high data rate operation, the ADC and digital equalization power consumption is a key concern in applications that support operation over a wide range of channels with varying amounts of intersymbol interference (ISI). This paper presents a hybrid ADC-based receiver architecture which employs a 3-tap analog feed-forward equalizer (FFE) embedded inside a 6 bit asynchronous successive approximation register (SAR) ADC and a per-symbol dynamically enabled digital equalizer, resulting in both reduced equalizer complexity and power consumption. Fabricated in general purpose (GP) 65 nm CMOS, the hybrid ADC-based receiver occupies area. 10 Gb/s operation is verified for FR4 channels with up to 36.4 dB attenuation, with the proposed dynamic enabling of the digital 4-tap FFE and 3-tap decision feedback equalizer (DFE) on a per-symbol basis resulting in nearly 30 mW savings and an overall receiver power less than 90 mW.
Autors: Shafik, A.;Zhian Tabasy, E.;Cai, S.;Lee, K.;Hoyos, S.;Palermo, S.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 671 - 685
Publisher: IEEE
 
» A 10 MHz Bandwidth, 70 dB SNDR Continuous Time Delta-Sigma Modulator With Digitally Improved Reconfigurable Blocker Rejection
Abstract:
This paper presents a continuous-time third-order low-pass delta-sigma modulator (DSM) with digitally enhanced out-of-band (OOB) signal filtering for enhanced blocker rejection in receiver analog-to-digital converters (ADCs). It is well known that strong OOB interferers define the required dynamic range (DR) of a receiver. Usually, a channel-select filter (CSF) is therefore required, together with the succeeding ADC. The feedback-compensated DSM can relax the CSF with its signal transfer characteristic. In this work, this is improved with a reconfigurable digital filter, which modifies the feedback signal of the outer-loop DAC to increase the OOB blocker rejection of the modulator. As a proof of concept, the digitally improved blocker rejection is shown in a prototype design. Additionally, a reconfigurable excess loop delay compensation technique based on an adaptive delay-locked-loop (DLL) has been implemented. The prototype is realized in a 90 nm CMOS technology, works at 480 MHz clock frequency, requires an area of , and achieves an in-band (IB) SNDR of 70 dB in a bandwidth of 10 MHz with a power consumption less than 14.4 mW. In the prototype, a digitally reconfigurable blocker rejection is realized achieving 6 dB additional suppression from 20 or 40 MHz on, or even 25 dB at the specific frequency of 20 MHz.
Autors: Ritter, R.;Kauffman, J.G.;Becker, J.;Ortmanns, M.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 660 - 670
Publisher: IEEE
 
» A 10-Gb/s 0.71-pJ/bit Forwarded-Clock Receiver Tolerant to High-Frequency Jitter in 65-nm CMOS
Abstract:
This brief presents a power-efficient forwarded-clock receiver that is tolerant to high-frequency jitter by mixing filtered clock jitter to data. Due to mixing the filtered clock jitter, the proposed receiver does not include power-hungry delay lines but a phase interpolator, which enables saving significant power consumption. In a prototype receiver implemented in a 1-V 65-nm complementary metal–oxide–semiconductor process, it removes 2-GHz 0.7UI jitter modulated in data by an amount of 22%. It achieves 10 Gb/s with 0.71 pJ/bit in 10-cm FR4 channels and occupies 0.012 mm 2.
Autors: Chung, Sang-Hye;Kim, Young-Ju;Kim, Yong-Hun;Kim, Lee-Sup;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Mar 2016, volume: 63, issue:3, pages: 264 - 268
Publisher: IEEE
 
» A 12.5-ENOB 10-kS/s Redundant SAR ADC in 65-nm CMOS
Abstract:
This brief describes a 14-b 10-kS/s successive approximation register analog-to-digital converter (ADC) for biomedical applications. In order to achieve enhanced linearity, a uniform-geometry nonbinary-weighted capacitive digital-to-analog converter is implemented. In addition, a secondary-bit approach to dynamically shift decision levels for error correction is employed. To reduce the power consumption, the ADC also features a power-optimized comparator with bias control. Prototyped in a 65-nm CMOS process, the ADC consumes 1.98 and provides an effective number of bit (ENOB) of 12.5 b at 0.8 V while occupying an active area of 0.28 mm 2.
Autors: Zhang, D.;Alvandpour, A.;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Mar 2016, volume: 63, issue:3, pages: 244 - 248
Publisher: IEEE
 
» A 2.4 GHz 4 mW Integer-N Inductorless RF Synthesizer
Abstract:
The high phase noise of ring oscillators has generally discouraged their use in RF synthesis. This paper introduces an integer-N synthesizer that employs a type-I loop to achieve a wide bandwidth, allowing the use of ring oscillators, and a master-slave sampling loop filter along with harmonic traps to suppress spurs. A 2.4 GHz prototype fabricated in 45 nm digital CMOS technology provides a loop bandwidth of 10 MHz and a spur level of . The phase noise is at 1 MHz offset.
Autors: Kong, L.;Razavi, B.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 626 - 635
Publisher: IEEE
 
» A 2D-3D Display With a 120-Hz Hybrid Spatial-Temporal Color LCD
Abstract:
A hybrid spatial-temporal color (STC) 2D-3D display is proposed using a 120-Hz liquid crystal panel with two color filters and light emitting diode matrix backlight. 3D mode was added to a Two Fields and Two Color Filters (2F2CF) STC LCD without adding any hardware element. This new configuration has 1.5 times higher resolution and around 1.5 times higher light efficiency than other currently used commercial 2D-3D LCDs because only two color filters are used. The backlight power consumption could be further reduced by applying the local dimming technology. The performances of the display with different backlight resolutions were analyzed with simulation on the aspect of image quality and power consumption. A perceptual experiment was also carried out to investigate the visual perception of stereoscopic impression, color nature and visual comfort by simulating specially at 3D mode. To balance the image quality and cost, 18 32 backlight segments was suggested for the optimal configuration.
Autors: Weng, Y.;Zhang, Y.;Li, X.;Wang, J.;
Appeared in: Journal of Display Technology
Publication date: Mar 2016, volume: 12, issue:3, pages: 294 - 301
Publisher: IEEE
 
» A 35 dBm Output Power and 38 dB Linear Gain PA With 44.9% Peak PAE at 1.9 GHz in 40 nm CMOS
Abstract:
This paper presents a 1.9 GHz linear power amplifier (PA) architecture that improves its power efficiency in the power back-off (PBO) region. The combination of power transistor segmentation and digital gain compensation effectively enhances its power efficiency. A fast switching scheme is proposed, such that PA drivers and segments are switched on and off according to signal power; thus, the PA power consumption correlates with the power of the input signal. Binary power gain variations due to PA segmentation are dynamically compensated in the digital domain. The proposed solution overcomes the tradeoffs between power efficiency and linearity by employing the digital predistortion technique. The PA is implemented in a 40 nm CMOS process. It delivers a saturated output power of 35 dBm with 44.9% peak power-added efficiency (PAE) and a linear gain of 38 dB. The adjacent channel leakage ratio (ACLR) at at a maximum linear output power of 31 dBm for a baseband WCDMA signal is .
Autors: Qian, H.;Liu, Q.;Silva-Martinez, J.;Hoyos, S.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 587 - 597
Publisher: IEEE
 
» A 4–32-GHz Chipset for a Highly Integrated Heterodyne Two-Port Vector Network Analyzer
Abstract:
This work presents a chipset for a highly integrated heterodyne vector network analyzer (VNA) with two ports and a multi-octave bandwidth from 4 to 32 GHz. The chipset is comprised of a stimulus integrated circuit (IC) with two selectable single-ended output channels and a four-channel receiver IC. Both chips contain a frequency synthesizer with an average output power of 2.5 dBm and a single-sideband phase noise between and at 1-MHz offset. The synthesizer consists of an array of three voltage-controlled oscillators with tuning ranges between 24.8% and 28.2% and a bandwidth extension stage. Wideband design techniques based on cascaded emitter followers are applied to a variable gain amplifier with a peak gain of 15.1 dB and to a wideband source switch with a minimum isolation of 23.6 dB. Single-ended receiver components such as a wideband low-noise amplifier with an average gain of 10 dB and a micromixer are used to compose the four-channel receiver with an average conversion gain of 14.4 dB. A hybrid microwave integrated circuit was fabricated in order to prove the functionality of a VNA utilizing the proposed chipset and wideband directional couplers. The measured scattering parameters of an arbitrary device-under-test showed an average deviation of 0.18 dB in magnitude and 1.8 in phase from the measurements obtained with a commercial VNA.
Autors: Nehring, J.;Dietz, M.;Aufinger, K.;Fischer, G.;Weigel, R.;Kissinger, D.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2016, volume: 64, issue:3, pages: 892 - 905
Publisher: IEEE
 
» A 55-GHz-Bandwidth Track-and-Hold Amplifier in 28-nm Low-Power CMOS
Abstract:
This brief presents a 25-GS/s track-and-hold amplifier (THA) implemented in a 28-nm low-power digital CMOS process. Given the intrinsic low-pass behavior of the THA core, a frequency compensation technique is employed to improve the bandwidth by increasing the input amplitude for higher frequencies. This enhances the small-signal bandwidth by almost 30% to 70 GHz. Large-signal measurements show a 3-dB corner frequency of 55 GHz, which enables a performance sufficient for time-interleaved analog-to-digital converter systems operating above 100 GS/s. At a peak-to-peak input amplitude of 400 mV, the total harmonic distortion is −32 dB for a 50-GHz input signal at a dc power consumption of 73 mW.
Autors: Tretter, G.;Fritsche, D.;Khafaji, M.;Carta, C.;Ellinger, F.;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Mar 2016, volume: 63, issue:3, pages: 229 - 233
Publisher: IEEE
 
» A 6-DOF Measurement Solution for Permanent Magnet Synchronous Planar Motors Based on Motion Continuity Principle
Abstract:
Exploiting motor-inherent magnetic field for displacement measurement has been paid much attention as it can greatly reduce setup complexity. In this paper, a successive solving iterative algorithm based on the magnetic field detection model and motion continuity is proposed for 6-DOF displacement measurement of the permanent magnet synchronous planar motor. A convergence theorem is given to ensure convergence of the algorithm. On the basis convergence conditions independent with the desired displacement are derived. Furthermore convergence (iteration) rate is given from an engineering point of view. Simulations are carried out to evaluate the feasibility and robustness to noise and parameter deviation of the algorithm. Translational comparison experiments with commercial displacement sensors are conducted on a self-developed experimental platform, and the experimental results verified the feasibility of the proposed method. The results of repeated measurement experiments on fixed positions show that compared with the commercial sensors, the mean of measurement deviation is 100- scale in both the - and -directions, and the standard deviation is better than 4.5 and 3 in the - and -directions, respectively. The implementation simplicity and the favorable measurement accuracy make the proposed method attractive for 6-DOF applications with large planar travel ranges, such as semiconductor manufacturing equipment and inspection equipment of printed circuit boards.
Autors: Chen, L.;Hu, J.;Zhu, Y.;Du, S.;Chai, Y.;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Mar 2016, volume: 65, issue:3, pages: 643 - 655
Publisher: IEEE
 
» A 69 dB SNDR, 25 MHz BW, 800 MS/s Continuous-Time Bandpass Modulator Using a Duty-Cycle-Controlled DAC for Low Power and Reconfigurability
Abstract:
A center frequency reconfigurable continuous-time bandpass modulator is implemented in 65 nm CMOS. A new duty-cycle-controlled DAC scheme facilitates center frequency reconfiguration, and also reduces power consumption and die area by halving the total number of DACs in the modulator. A prototype sixth-order modulator, sampling at 800 MS/s, achieves a measured 69 dB SNDR over a 25 MHz bandwidth around a 200 MHz center frequency. The center frequency of the prototype bandpass modulator can be varied from 180 to 220 MHz. The total power consumption is 35 mW and the die area is 0.25 . This modulator scheme facilitates receivers that support multiple channels over a wide range of frequencies.
Autors: Chae, H.;Flynn, M.P.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 649 - 659
Publisher: IEEE
 
» A 79-GHz Adaptive-Gain and Low-Noise UWB Radar Receiver Front-End in 65-nm CMOS
Abstract:
A 79-GHz adaptive-gain and low-noise ultra-wideband radar receiver RF front-end integrated circuit in 65-nm CMOS is presented in this paper. The receiver consists of an adaptive-gain low-noise amplifier (AGLNA) and a -boosted sub-harmonic mixer (SHM). The proposed AGLNA controls the gain with adaptive biased circuits, which lowers the gain as the received signal power increases to provide wide dynamic range to the radar receiver without any external controls. We analyzed the input impedance of a cascode amplifier with a parallel resonant inductor, which improves the noise figure. The proposed -boosted SHM uses a transformer-based feedback network with NMOS bleeding circuits to provide a high conversion gain. The SHM was designed to use a differential local oscillator (LO) signal to have a simple structure and operate at low LO power. The measured conversion gain range was from 16 to with a received power range from to at 79.5 GHz. The measured noise figure was 10.5 dB and the measured 2LO-to-RF isolation was 70 dB. The chip area is .
Autors: Jang, J.;Oh, J.;Kim, C.-Y.;Hong, S.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2016, volume: 64, issue:3, pages: 859 - 867
Publisher: IEEE
 
» A Batch-Based MAC Design With Simultaneous Assignment Decisions for Improved Throughput in Guard-Band-Constrained Cognitive Networks
Abstract:
The adjacent channel interference (ACI) resulting from imperfect filtering can severely degrade the performance of any wireless communication system. Despite this fact, most of previously proposed medium access control (MAC) protocols for cognitive radio networks (CRNs) were designed while ignoring the effects of ACI (assuming ideal filtering). The effect of ACI can be reduced by introducing guard bands (GBs). However, this solution comes at the expense of degrading spectrum efficiency. In this paper, we develop an efficient GB-aware MAC protocol that attempts at maximizing network throughput while improving fairness in CRNs. Unlike most of previously proposed GB-aware MAC protocols that perform channel assignment sequentially, our MAC performs the channel assignment for multiple CR links simultaneously (the so-called batch method). Batching enables concurrent channel assignment for multiple CR links, which consequently allows for concurrent data transmissions. Batching can be realized by introducing an admission control phase for CR users to share their control information. The batch method can effectively provide distributed decisions that achieve better throughput while reducing the number of GBs. Our MAC also allows the CR users to utilize the reserved GBs of primary networks under predefined FCC power constraints. Simulation results indicate that our protocol achieves significant performance improvement compared to previous GB-aware protocols.
Autors: Bany Salameh, H.;Kasasbeh, H.;Harb, B.;
Appeared in: IEEE Transactions on Communications
Publication date: Mar 2016, volume: 64, issue:3, pages: 1143 - 1152
Publisher: IEEE
 
» A Bayesian Approach for One-Shot Device Testing With Exponential Lifetimes Under Competing Risks
Abstract:
This paper considers a competing risk model for a one-shot device testing analysis under an accelerated life test setting. Due to the consideration of competing risks, the joint posterior distribution becomes quite complicated. The Metropolis-Hastings sampling method is used for the estimation of the posterior means of the variables of interest. A simulation study is carried out to assess the Bayesian approach with different priors, and also to compare it with the EM algorithm for maximum likelihood estimation. Finally, an example from a tumorigenicity experiment is presented.
Autors: Balakrishnan, N.;So, H.Y.;Ling, M.H.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2016, volume: 65, issue:1, pages: 469 - 485
Publisher: IEEE
 
» A Benchmark Evaluation of Similarity Measures for Multitemporal SAR Image Change Detection
Abstract:
Synthetic aperture radar (SAR) image change detection is playing an important role in various Earth Observation (EO) applications. There exists a large number of different methods that have been proposed to address this issue. However, due to the fact that several kinds of changes with diverse characteristics can arise in SAR images, there is no consensus on their performances because most methods have been evaluated using different data sets, probably facing several kinds of changes, but without an in-depth analysis of the characteristics of SAR image changes. Therefore, two important problems arise. The first is what kind of change each approach can detect. The second is how much they can detect a kind of change. Although the importance to model any kind of changes has been realized, there is no principled methodology to carry out the analysis due to the difficulty in modeling various kinds of changes. In this paper, we propose a benchmark methodology to reach this goal by simulating selected kinds of changes in addition to using real data with changes. Six kinds of SAR changes for eight typical image categories are simulated, i.e., reflectivity changes, first-order, second-order, and higher order statistical changes, linear and nonlinear changes. Based on this methodology for change simulation, a comprehensive evaluation of information similarity measures is carried out. An explicit conclusion we have drawn from the evaluation is that the various methods behave very differently for all kinds of changes. We hope that this study will promote the advancement of this topic.
Autors: Cui, S.;Schwarz, G.;Datcu, M.;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Mar 2016, volume: 9, issue:3, pages: 1101 - 1118
Publisher: IEEE
 
» A Bonded-Type Piezoelectric Actuator Using the First and Second Bending Vibration Modes
Abstract:
A piezoelectric actuator, which is constructed by bonding six pieces of lead zirconate titanate (PZT) ceramic plates on a step aluminum alloy beam, was proposed and tested for the design of a small-size rotary driving appratus. Two pieces of PZT ceramic plates bonded in the middle part is used to generate the first bending mode, whereas the other four on the two sides are set for the excitation of the second bending mode; their superimposition can produce elliptical movements on the two ends of the beam, which can rotate a disk-shaped rotor. Compared with the traditional ring-shaped traveling-wave piezoelectric actuator, the proposed actuator has a simpler structure and operating principle; it also gives a new mode for rotary driving. The resonance frequencies of the first and second bending modes were designed to be close at about 21.1 kHz. The maximum no-load speed and torque were tested to be 158 r/min and 0.053 , respectively. The prototype achieved a power density of 19.0 W/kg under a weight of 15.8 g. The proposed combination plan of the first and second bending modes is very suitable for constructing a small-size piezoelectric actuator, which exhibits merits for application in small systems.
Autors: Liu, Y.;Yang, X.;Chen, W.;Xu, D.;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Mar 2016, volume: 63, issue:3, pages: 1676 - 1683
Publisher: IEEE
 
» A Boundary Integral Method for Computing Eddy Currents in Non-Manifold Thin Conductors
Abstract:
We introduce a novel technique to solve eddy current problems in non-manifold thin conductors by a boundary integral method based on a stream function. The idea is to perform a surgery on the non-manifold surface representing the thin conductor to reduce it into a minimal number of manifold parts. Then, manifold parts are stitched together by adding constraints, which ensure that the discrete current continuity law holds.
Autors: Bettini, P.;Dlotko, P.;Specogna, R.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Broadband Mixed-Signal CMOS Power Amplifier With a Hybrid Class-G Doherty Efficiency Enhancement Technique
Abstract:
This paper presents a broadband mixed-signal CMOS power amplifier (PA) with a hybrid Class-G Doherty architecture for PA efficiency enhancement up to the deep power back-off (PBO) region. Our proposed mixed-signal linearization technique ensures the PA’s amplitude modulation (AM)–AM linearity by digital PA operation and suppresses the PA’s AM–phase modulation (PM) nonlinearity by real-time analog phase compensation. The PA is fully integrated in a standard 65 nm bulk CMOS process, and achieves a peak output power () of with a 40.2% peak drain efficiency (DE) at 3.71 GHz. The DE at 6 and 12 dB PBO is and over the reference Class-B PA operation, advancing the state-of-the-art CMOS PA PBO efficiency performance. The PA 1 dB bandwidth is extended from 1.08 to 1.8 GHz by reconfiguring the phase difference between the main and auxiliary paths in the Doherty PA. In the modulation measurements with 1 MSym/s 16 QAM signals, the PA performs dynamic hybrid Class-G Doherty operation and achieves peak with 28.8% DE at 3.71 GHz and efficiency enhancement at 8.1 dB PBO over Class-B operation. The real-time AM–PM linearization technique achieves 3.3 and 2.9 dB improvements on the EVM and adjacent channel leakage ratio (ACLR), respectively. The broadband- Class-G Doherty operation is also demonstrated with modulated signals.
Autors: Hu, S.;Kousai, S.;Wang, H.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 598 - 613
Publisher: IEEE
 
» A Cascaded Linear High-Voltage Amplifier Circuit for Dielectric Measurement
Abstract:
High-voltage amplifiers have the features of high output voltage, wide frequency bandwidth, and desirable linearity. It is widely used for dielectric measurement in industrial and laboratory applications. This paper presents a new type of cascaded high-voltage amplifier with a voltage gain of 40 times for one circuit cell. The unit circuit is given in detail, which is based on an isolation circuit with linear opto-coupler and an amplified circuit with six operational amplifiers. The negative feedback and capacitive loads characteristics are analyzed theoretically. The step response and frequency curves for two units of amplifier circuit have been tested physically in laboratory. The test results show that the expected voltage gain within the frequency range from 10-3 to 104 can be obtained accurately. The new type of linear high-voltage amplifier circuit proposed in this paper is also helpful to insulation diagnosis, electrostatic deflection, and other industrial applications.
Autors: Liu, J.;Zhang, D.;Wang, M.;Huang, L.;Zhao, D.;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Mar 2016, volume: 63, issue:3, pages: 1834 - 1841
Publisher: IEEE
 
» A Class of Quadrature Couplers Based on Transformer
Abstract:
A study of lumped transformer-based directional couplers is proposed by converting a conventional two-port transformer into a four-port directional coupler. The directional coupler of this kind is a backward coupler that consists of a ferrite-core transformer and four or five associated lumped reactive elements. Four different topologies of the coupler are proposed with four different reactive element arrangements, namely, ring topology, cross topology, H-shaped topology, and twisted topology. Analysis and design equations are presented. Four different circuits with different frequency responses are derived. Four 13.56-MHz couplers with these four different topologies are designed, fabricated, and measured. Wideband, compact, and backward wave coupling features are theoretically and experimentally confirmed.
Autors: Hou, Z.J.;Chiu, L.;Xue, Q.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2016, volume: 64, issue:3, pages: 785 - 797
Publisher: IEEE
 
» A Column-Row-Parallel ASIC Architecture for 3-D Portable Medical Ultrasonic Imaging
Abstract:
This paper presents a scalable column-row-parallel ASIC architecture for 3-D portable medical ultrasound. Through its programmable row-by-row or column-by-column operations for both transmit and receive beam-formation, linear scaling in interconnection, data acquisition complexity, power dissipation, and programming time is achieved. In addition, its per-element controllers can activate fine granularity aperture definition when more functionality is favored over the linear-scaling power and speed efficiency. This front-end architecture is backward compatible to implement existing widely used array aperture patterns, while supporting new imaging apertures and algorithms. It lends itself very well for the combination with integrated or external digital beamforming circuits. A proof-of-concept ASIC is fabricated and flip-chip bonded to a capacitive micromachined ultrasonic transducer (CMUT). Each three-level pulsing transmitter (Tx) is 46% more power efficient than a traditional two-level version, with high-voltage (HV) multiplexers (MUXs) designed for flexible Tx parallelization. Each low-noise receiver (Rx) consumes 1.4 mW active power and sleep power, with optimized source follower stages to combine analog outputs for improved SNR. The transceivers are also fault-tolerant to inevitable defects in transducers, greatly enhancing assembly yield. The system demonstrates 3-D plane-wave generation to implement the coherent compounding algorithm for fast volume rate (62.5 volume/s), high-quality 3-D ultrasonic imaging. An interleaved checker board pattern with and excitations is also demonstrated for ultrasonic harmonic imaging, which reduces transmitted second harmonic distortion (HD2) by over 20 dB.
Autors: Chen, K.;Lee, H.-S.;Sodini, C.G.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 738 - 751
Publisher: IEEE
 
» A Combinational-Logic Method for Electric Vehicle Drivetrain Fault Diagnosis
Abstract:
This paper presents a combinational-logic-based approach for identifying faults that could occur in the drivetrain of an electric vehicle (EV). A real-time simulation model of an EV is used to study the behavior of available sensor signals and control commands, with specific measured quantities, during vehicle operation. Those quantities could be, but are not limited to, mean values of the phase currents, DC bus current, traction motor speed (if available), in addition to control command quantities. Focus is given to these quantities which are abundant in vehicle inverters and controllers for no added sensing costs. Those quantities carry information of offsets and disturbances that could occur under faulty operating conditions compared to nominal operation, and are thus observed and studied under these conditions. Using such information, a method is developed using simple combinational logic and thresholds to diagnose a fault occurring at any time during a vehicle drive cycle. By combining features of measured quantities that behave similarly irrespective of when the fault occurs during a driving cycle, the proposed method is fault-time-insensitive. The proposed method is presented and validated by real-time simulations to capture over 20 different faults injected at different drive cycle times and in different drivetrain components—electric machine, inverter, transmission, and sensors. Results show that the proposed method is able to robustly and successfully diagnose different faults irrespective of when would they occur.
Autors: Ulatowski, A.;Bazzi, A.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2016, volume: 52, issue:2, pages: 1796 - 1807
Publisher: IEEE
 
» A Comment on the Beta Hazard Rate Distribution
Abstract:
We point out that the beta hazard rate distribution introduced by Lai and Jones is a particular case of Libby and Novick's beta distribution known since 1982.
Autors: Nadarajah, S.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2016, volume: 65, issue:1, pages: 158 - 158
Publisher: IEEE
 
» A Compact Portable Microwave Life-Detection Device for Finding Survivors
Abstract:
In this letter, an ultra-sensitive compact portable microwave life-detection device is introduced and implemented with promising results. By utilizing Doppler effect-based systems, vital signs such as heartbeats and breathing can be detected and can be used for finding survivors under earthquake rubble, injured soldiers on battlefields and as lie detection device. This device is tested in both simulated and realistic situations, and it can accurately detect crucial signs of life through highly dense construction materials of about 1.5 m thick and standard density materials of about 10 m while operating at 1.15 GHz center frequency.
Autors: JalaliBidgoli, F.;Moghadami, S.;Ardalan, S.;
Appeared in: IEEE Embedded Systems Letters
Publication date: Mar 2016, volume: 8, issue:1, pages: 10 - 13
Publisher: IEEE
 
» A Comparative Study on Probabilistic Optimization Methods for Electromagnetic Design
Abstract:
A reliability-based robust design optimization (RBRDO) is developed to ensure the product quality as well as the confidence in product reliability of electromagnetic devices. In the method, the first two statistical moments, mean and variance, of a quality loss function are estimated by the univariate dimension reduction method, while desired probabilistic constraint conditions are assessed by one of the first-order reliability analysis methods, called performance measure approach. For a better understanding between probabilistic design optimization methods, three different formulations of reliability-based design optimization, robust design optimization (RDO), and RBRDO are compared with one another. A simple mathematical model and a brushless direct current (BLDC) motor design problem are tested to demonstrate the features of the three methods and to examine their numerical efficiency.
Autors: Kim, D.;Kang, B.;Choi, K.K.;Kim, D.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Comparison Among Low Temperature Piezoelectric Flexible Sensors Based on Polysilicon TFTs for Advanced Tactile Sensing on Plastic
Abstract:
In this work, we present a comparison among four different piezoelectric materials (PVDF-TrFE, Piezopaint, AlN and ZnO), all deposited at low temperature (from RT up to 160 ) on flexible substrate such as thin Polyimide, in order to investigate their possible implementation as flexible tactile sensors. Flexible capacitive sensors were tested by using a mini-shaker, investigating the sensors behavior in force and frequency with the intent of mimicking the human sense of touch. We optimized the piezoelectric properties of the materials by using specific texturing buffer layers or maximizing the poling procedure to increase the dipole alignment. Finally, by using a multi-foil approach, the different sensors have been integrated with polysilicon thin film transistor fabricated on flexible substrates and the specific device sensitivity was evaluated.
Autors: Maiolo, L.;Maita, F.;Pecora, A.;Minotti, A.;Fortunato, G.;Smecca, E.;Alberti, A.;
Appeared in: Journal of Display Technology
Publication date: Mar 2016, volume: 12, issue:3, pages: 209 - 213
Publisher: IEEE
 
» A Comparison of Alloy-Surface Finish Combinations Considering Different Component Package Types and Their Impact on Soldering Reliability
Abstract:
Reliability specifications for solder joints, as well as for all electronic components, have become a fundamental feature in the qualification of an electronic product. The relevance of these reliability features increases if new components or materials are considered. In this research activity, an accelerated thermal test on customized electronic boards was implemented for an early reliability evaluation; we therefore proposed a study on the reliability behavior of a solder joint by considering different surface finishes, and several component packages. A comparative study was carried out through the application of statistical methods. To this end, Weibull distributed data and non-linear mixed models were evaluated. More precisely, Weibull random-effects models were applied to compare different combinations of surface finishes, (e.g. Hot Air Solder Leveling, Electroless Nickel Immersion Gold, Immersion Tin) and alloys, (e.g. tin-silver-copper, tin-lead), connected to four types of components, also to evaluate how the type of package or the geometry of the joint may affect the reliability of the soldering. Therefore, the aim of this research is a statistical study of the reliability of solder alloys subjected to thermal aging tests by also taking different surface finishes of the printed circuit boards and different types of packaging into account. The study was carried out with two-by-two comparisons of alloy-surface finishes. By evaluating the statistical results, the tin-silver-copper alloy, with the considered finishes, demonstrates a higher reliability with respect to the boards soldered by the traditional combination of soldering alloy and surface finish.
Autors: Berni, R.;Catelani, M.;Fiesoli, C.;Scarano, V.L.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2016, volume: 65, issue:1, pages: 272 - 281
Publisher: IEEE
 
» A Comprehensive Magnet Defect Fault Analysis of Permanent-Magnet Synchronous Motors
Abstract:
In this paper, magnet defect faults and their corresponding reflections on permanent-magnet (PM) motor stator variables are investigated. An analytical approach based on a partitioned magnetic equivalent circuit is developed to determine the influence of magnet defect faults on PM motor variables. Due to the flexibility of the proposed method, the effect of each rotor magnets on each stator coil can be calculated to obtain the induced back electromotove force under faulty cases and observe the fault-related signatures in the frequency spectrum. The proposed tool significantly reduces the computational burden and provides sufficient accuracy, which significantly eases to simulate several magnet fault scenarios and examine detailed topology dependence relations in shorter time. Different cases, including various numbers and locations of defected magnets, winding configurations, and crack direction effects, are studied to understand the magnet defect influences comprehensively. The experiments and simulations are carried out at different speeds and load conditions to fully characterize the fault signatures. Comparative 2-D finite-element simulations and experimental results justify the theoretical magnet defect fault analysis and show the efficacy of the proposed approach.
Autors: Zafarani, M.;Goktas, T.;Akin, B.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2016, volume: 52, issue:2, pages: 1331 - 1339
Publisher: IEEE
 
» A Computational Approach for a Wireless Power Transfer Link Design Optimization Considering Electromagnetic Compatibility
Abstract:
This paper presents an electromagnetic-artificial intelligence design optimization approach of a wireless power transfer link (WPTL). Electromagnetic solutions from a 3-DFE model of the WPTL were utilized to minimize the field signature around each design while maintaining high efficiency. The reduced field signatures around the WPTL would enable the achievement of designs that are in accordance with international electromagnetic compatibility (EMC) standards such as international commission on non-ionizing radiation protection guidelines with respect to public exposure levels of EM signatures below 27 . As the optimization process involved utilizing a large number of fitness function evaluations, numerous 3-DFE solutions were required increasing the computational burden. Artificial neural networks were developed, trained, and used to produce the required equivalent 3-DFE solutions to evaluate the fitness function. As a result, this process significantly reduced the computational time by nearly 90%. The genetic algorithm-based optimization process yielded the desired results of electromagnetically compatible WPTL designs at the early development stage satisfying EMC standards.
Autors: Hariri, A.O.;Youssef, T.;Elsayed, A.;Mohammed, O.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Computationally Efficient Algorithm for Rotor Design Optimization of Synchronous Reluctance Machines
Abstract:
A generalizable algorithm is proposed for the design optimization of synchronous reluctance machine rotors. Single-barrier models are considered to reduce the algorithm’s computational complexity and provide a relative comparison for rotors with different slots-per-pole combinations. Two objective values per sampled design (average and ripple torques) are computed using 2-D finite-element analysis simulations. Non-linear regression or surrogate models are trained for the two objectives through a Bayesian regularization backpropagation neural network. A multi-objective genetic algorithm is used to find the validated Pareto front solutions. An analytical ellipse constraint is then suggested to encapsulate optimal solutions. Compared with a direct sampling approach, this restriction captures an optimal region within the double-barrier space for further torque ripple reduction.
Autors: Mohammadi, M.H.;Rahman, T.;Silva, R.;Li, M.;Lowther, D.A.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Computer-Supported Collaborative Learning Design for Quality Interaction
Abstract:
This study investigated, through both formative and practical evaluation, the relationships among the use of functions in computer-supported collaborative learning (CSCL), psychological factors, and learning behaviors related to applying the Community of Inquiry (CoI) framework. The goal was to increase active interaction among learners. In two experiments inside and outside the classroom, the authors examined an online discussion and collected data using questionnaires that assessed perceived psychological factors, as well as communication logs related to the efficacy of CoI. The results of a path analysis showed two points. First, cognitive learning tools support the enhancement of expressive cognitive presence that promotes the perception of CoI as formative evaluation. Second, the frequency of the use of the functions fostered expressive social and cognitive presence (which enhanced the perception of both), perceived contribution, and satisfaction with online discussion. This article is part of a special issue on social media for learning.
Autors: Yamada, Masanori;Goda, Yoshiko;Matsukawa, Hideya;Hata, Kojiro;Yasunami, Seisuke;
Appeared in: IEEE Multimedia
Publication date: Mar 2016, volume: 23, issue:1, pages: 48 - 59
Publisher: IEEE
 
» A Constant Energy-Per-Cycle Ring Oscillator Over a Wide Frequency Range for Wireless Sensor Nodes
Abstract:
This paper presents an energy-efficient oscillator for wireless sensor nodes (WSNs). It avoids short-circuit current by minimizing the time spent in the input voltage range from to . A current-feeding scheme with gate voltage control enables the oscillator to operate over a wide frequency range. A test chip is fabricated in a CMOS process. The measurements show that the proposed oscillator achieves a constant energy-per-cycle (EpC) of 0.8 pJ/cycle over the 21–60 MHz frequency range and is more efficient than a conventional current-starved ring oscillator (CSRO) below 300 kHz at 1.8 V supply voltage. As an application example, the proposed oscillator is implemented in a switched-capacitor DC–DC converter. The converter is 11%–56% more efficient for load power values ranging from 583 pW to 2.9 nW than a converter using a conventional CSRO.
Autors: Lee, I.;Sylvester, D.;Blaauw, D.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2016, volume: 51, issue:3, pages: 697 - 711
Publisher: IEEE
 
» A Constrained Coalition Formation Game for Multihop D2D Content Uploading
Abstract:
This paper investigates relay-based schemes in cellular systems, where multihop device-to-device (D2D) communications are exploited for content uploading toward the eNodeB. All user equipments (UEs) are sources of their own content and form a multihop D2D chain, with the head of the chain being in charge of uploading all the generated content to the eNodeB. By pooling the cellular radio resources assigned to the D2D chain and by using high-quality short-range radio links, the proposed cooperative content uploading scheme guarantees lower upload delays than in the traditional cellular mode operation. To model the D2D chain formation in a cell and to best characterize self-interested users concerned about their own payoff, a constrained coalition formation game is defined, where each UE is a player whose cost is identified as the content upload time. The solution of the game determines the stable feasible partition for the UEs in the cell. We demonstrate through simulations that with this solution the content uploading time is reduced by 52% with respect to the traditional cellular mode.
Autors: Militano, L.;Orsino, A.;Araniti, G.;Molinaro, A.;Iera, A.;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Mar 2016, volume: 15, issue:3, pages: 2012 - 2024
Publisher: IEEE
 
» A Data-Driven Bias-Correction-Method-Based Lithium-Ion Battery Modeling Approach for Electric Vehicle Applications
Abstract:
Due to the inconsistent and varied characteristics of lithium-ion battery (LiB) cells, battery pack modeling remains a challenging problem. To model the operation of each cell in the battery pack, considerable work effort and computation time are needed. This paper proposes a data-driven bias-correction-based LiB modeling method, which can significantly reduce the computation work and remain good model accuracy.
Autors: Gong, X.;Xiong, R.;Mi, C.C.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2016, volume: 52, issue:2, pages: 1759 - 1765
Publisher: IEEE
 
» A Deep-Intelligence Framework for Online Video Processing
Abstract:
Video data has become the largest source of big data. Owing to video data's complexities, velocity, and volume, public security and other surveillance applications require efficient, intelligent runtime video processing. To address these challenges, a proposed framework combines two cloud-computing technologies: Storm stream processing and Hadoop batch processing. It uses deep learning to realize deep intelligence that can help reveal knowledge hidden in video data. An implementation of this framework combines five architecture styles: service-oriented architecture, publish-subscribe, the Shared Data pattern, MapReduce, and a layered architecture. Evaluations of performance, scalability, and fault tolerance showed the framework's effectiveness. This article is part of a special issue on Software Engineering for Big Data Systems.
Autors: Zhang, W.;Xu, L.;Li, Z.;Lu, Q.;Liu, Y.;
Appeared in: IEEE Software
Publication date: Mar 2016, volume: 33, issue:2, pages: 44 - 51
Publisher: IEEE
 
» A Defect-Centric Analysis of the Temperature Dependence of the Channel Hot Carrier Degradation in nMOSFETs
Abstract:
The defect-centric distribution is used to study the temperature dependence of channel hot carrier (CHC) degradation in deeply scaled nMOSFETs. We analyze the temperature dependence in terms of the defect-centric parameters. The total number of traps is observed to increase with temperature, whereas the average threshold voltage shift produced by a single charged defect, i.e., , is confirmed to be independent of the temperature, as previously shown for bias temperature instability. By using the defect-centric analysis, we estimate the activation energy of the threshold voltage shift and that of the number of charged traps per device, which are directly linked to the CHC degradation.
Autors: Procel, L.M.;Crupi, F.;Trojman, L.;Franco, J.;Kaczer, B.;
Appeared in: IEEE Transactions on Device and Materials Reliability
Publication date: Mar 2016, volume: 16, issue:1, pages: 98 - 100
Publisher: IEEE
 
» A Derivative Splitting Approach to Sensitivity Analysis of Magnet Design
Abstract:
This paper introduces an analytical approach for an effective evaluation of the variation of the magnetic field generated by complex coils due to deformations with respect to the nominal configuration. The coils are described with a set of synthetic design parameters, and the deformations can be described as variations of such parameters. This paper proposes a method to evaluate the derivatives of the magnetic field with respect to the design parameters by splitting them into a magnetic factor and a geometrical factor. A comparison with the classical finite-differences approach is carried out. This paper focuses on the context of sensitivity analysis, but the methodology is quite general and can easily be extended in other fields.
Autors: Chiariello, A.G.;Formisano, A.;Ledda, F.;Martone, R.;Pizzo, F.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Deterministic Analysis for LRR
Abstract:
The recently proposed low-rank representation (LRR) method has been empirically shown to be useful in various tasks such as motion segmentation, image segmentation, saliency detection and face recognition. While potentially powerful, LRR depends heavily on the configuration of its key parameter, λ. In realistic environments where the prior knowledge about data is lacking, however, it is still unknown how to choose λ in a suitable way. Even more, there is a lack of rigorous analysis about the success conditions of the method, and thus the significance of LRR is a little bit vague. In this paper we therefore establish a theoretical analysis for LRR, striving for figuring out under which conditions LRR can be successful, and deriving a moderately good estimate to the key parameter λ as well. Simulations on synthetic data points and experiments on real motion sequences verify our claims.
Autors: Liu, G.;Xu, H.;Tang, J.;Liu, Q.;Yan, S.;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Mar 2016, volume: 38, issue:3, pages: 417 - 430
Publisher: IEEE
 
» A Differential Evolution-Based Approach for Fitting a Nonlinear Biophysical Model to fMRI BOLD Data
Abstract:
Physiological and biophysical models have been proposed to link neuronal activity to the Blood Oxygen Level-Dependent (BOLD) signal in functional MRI (fMRI). Those models rely on a set of parameter values that cannot always be extracted from the literature. In some applications, interesting insight into the brain physiology or physiopathology can be gained from an estimation of the model parameters from measured BOLD signals. This estimation is challenging because there are more than 10 potentially interesting parameters involved in nonlinear equations and whose interactions may result in identifiability issues. However, the availability of statistical prior knowledge about these parameters can greatly simplify the estimation task. In this work we focus on the extended Balloon model and propose the estimation of 15 parameters using two stochastic approaches: an Evolutionary Computation global search method called Differential Evolution (DE) and a Markov Chain Monte Carlo version of DE. To combine both the ability to escape local optima and to incorporate prior knowledge, we derive the target function from Bayesian modeling. The general behavior of these algorithms is analyzed and compared with the de facto standard Expectation Maximization Gauss-Newton (EM/GN) approach, providing very promising results on challenging real and synthetic fMRI data sets involving rats with epileptic activity. These stochastic optimizers provided a better performance than EM/GN in terms of distance to the ground truth in 3 out of 6 synthetic data sets and a better signal fitting in 11 out of 12 real data sets. Non-parametric statistical tests showed the existence of statistically significant differences between the real data results obtained by DE and EM/GN. Finally, the estimates obtained from DE for these parameters seem both more realistic and more stable or at least as stable across sessions as the estimates from EM/GN.
Autors: Mesejo, P.;Saillet, S.;David, O.;Benar, C.G.;Warnking, J.M.;Forbes, F.;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Mar 2016, volume: 10, issue:2, pages: 416 - 427
Publisher: IEEE
 
» A Distance-Computation-Free Search Scheme for Binary Code Databases
Abstract:
Recently, binary codes have been widely used in many multimedia applications to approximate high-dimensional multimedia features for practical similarity search due to the highly compact data representation and efficient distance computation. While the majority of the hashing methods aim at learning more accurate hash codes, only a few of them focus on indexing methods to accelerate the search for binary code databases. Among these indexing methods, most of them suffer from extremely high memory cost or extensive Hamming distance computations. In this paper, we propose a new Hamming distance search scheme for large scale binary code databases, which is free of Hamming distance computations to return the exact results. Without the necessity to compare database binary codes with queries, the search performance can be improved and databases can be externally maintained. More specifically, we adopt the inverted multi-index data structure to index binary codes. Importantly, the Hamming distance information embedded in the structure is utilized in the designed search scheme such that the verification of exact results no longer relies on Hamming distance computations. As a step further, we optimize the performance of the inverted multi-index structure by taking the code distributions among different bits into account for index construction. Empirical results on large-scale binary code databases demonstrate the superiority of our method over existing approaches in terms of both memory usage and search efficiency.
Autors: Song, J.;Shen, H.T.;Wang, J.;Huang, Z.;Sebe, N.;Wang, J.;
Appeared in: IEEE Transactions on Multimedia
Publication date: Mar 2016, volume: 18, issue:3, pages: 484 - 495
Publisher: IEEE
 
» A Distributed Clustered Architecture to Tackle Delay Variations in Datapath Synthesis
Abstract:
Due to the necessity of handling unexpected events in execution time, e.g., to support process variations, new mechanisms for dealing with every possible behavior of the datapath must be developed. Conventional centralized controllers can only handle very few dynamic events. Distributed controllers, on the other hand, are able to support every combination of events. These controllers are composed of several finite state machines, which are interconnected via a global coordinator. The use of this type of controller obliges to check the hazards between operations in run time, which entails some penalty in the controller complexity. In this paper, a new methodology for deploying a distributed controller over a set of clusters is presented. A register binding algorithm specially suited for distributed controllers has also been developed. It combines a clustering method and a least recently used policy to reduce the number of hazards in run time. Furthermore, our methodology allows the exploration of different solutions by tuning the input parameters of the binding algorithm. Several studies evaluating the execution time and area tradeoffs are presented to support our techniques. Results show that for some cases it is possible to reduce more than 50% the expected execution time, at the expense of a slight area increase.
Autors: Del Barrio, A.A.;Cong, J.;Hermida, R.;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Mar 2016, volume: 35, issue:3, pages: 419 - 432
Publisher: IEEE
 
» A Double-Layer Transmitarray Antenna Using Malta Crosses With Vias
Abstract:
A novel transmitarray element consisting of only two layers of modified Malta crosses printed on a dielectric substrate is proposed, and vias are employed to augment the transmission magnitude and enhance its phase shift range. A prototype transmitarray with a circular aperture of 338 mm in diameter is then designed, fabricated, and tested to validate the proposed design. The simulation and measurement results show good radiation characteristics with measured gain of 33.0 dBi at 20 GHz and aperture efficiency of 40%. The proposed element considerably simplifies the complexity of a transmitarray, reducing its thickness, mass, and cost.
Autors: an, w.;Xu, S.;Yang, F.;Li, M.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2016, volume: 64, issue:3, pages: 1120 - 1125
Publisher: IEEE
 
» A Droop Control Design for Multiterminal HVDC of Offshore Wind Farms With Three-Wire Bipolar Transmission Lines
Abstract:
Converting existing ac transmission lines to an extended multiterminal three-wire bipolar HVDC system can be considered a cost-effective way to interconnect dispersed offshore wind farms to onshore ac grids instead of building new bipolar HVDC systems. To automatically coordinate between different converters in a multiterminal HVDC (MTDC) system, droop control techniques have been adopted as an effective means without the need for fast communications between units. The droop control design is mainly dependent on the line resistances. This paper shows that the equivalent resistance of a three-wire bipolar system changes based on the operational mode. The modification to droop control design of an MTDC equipped with a three-wire bipolar system is then presented to tackle this resistance variation with the operating condition. Two types of MTDC systems are considered in this work, namely, radial parallel and meshed parallel systems. Different simulation studies have been conducted to validate the results of the presented analysis.
Autors: Abdel-Khalik, A.S.;Abu-Elanien, A.E.B.;Elserougi, A.A.;Ahmed, S.;Massoud, A.M.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Mar 2016, volume: 31, issue:2, pages: 1546 - 1556
Publisher: IEEE
 
» A Dual Kriging Approach With Improved Points Selection Algorithm for Memory Efficient Surrogate Optimization in Electromagnetics
Abstract:
This paper introduces a new approach to kriging surrogate model sampling points allocation. By introducing the second (dual) kriging during the model construction, the existing sampling points are reallocated to reduce overall memory requirements. Moreover, a new algorithm is proposed for selecting the position of the next sampling point by utilizing a modified expected improvement criterion.
Autors: Li, Y.;Xiao, S.;Rotaru, M.;Sykulski, J.K.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Dynamic Cell Clustering Algorithm for Maximization of Coordination Gain in Uplink Coordinated System
Abstract:
We propose a dynamic clustering algorithm for maximizing a coordination gain in the uplink coordinated system. The dynamic clustering algorithm configures clusters periodically to adopt the change of the channel environment. Since the greedy-search clustering algorithm does not guarantee cell-edge users' performance and the full-search clustering algorithm (FSCA) is highly complex, we define a coordination gain between the coordinated communication system and the single-cell communication system, as a new parameter, to maximize the benefit of the coordinated communication system. We develop a maximum coordination gain (MAX-CG) clustering algorithm to maximize the coordination gain and an interference weight (IW) clustering algorithm to reduce complexity and guarantee the data rate of cell-edge users. Simulation results show that the MAX-CG clustering algorithm improves the average user rate and the 5% edge user rate. The IW clustering algorithm improves the 5% edge user's rate, guarantees the fairness among the cells, and reduces the complexity to only half of the existing algorithm.
Autors: Yoon, M.;Kim, M.;Lee, C.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Mar 2016, volume: 65, issue:3, pages: 1752 - 1760
Publisher: IEEE
 
» A Dynamic Dual-Response-Surface Methodology for Optimal Design of a Permanent-Magnet Motor Using Finite-Element Method
Abstract:
This paper presents an approach for improving the process of optimal design of permanent-magnet (PM) motors. A finite-element method (FEM) combined with a dynamic dual-response-surface model (dual-RSM) is proposed to compute an objective function. The FEM is employed as a basic tool for the computation of the objective function. In order to build up the dual-RSM model, a radial basis function and a moving least-square approximation are both employed. The results that are obtained from the dual-RSM model are dynamically compared together with a preset goodness-of-fit, which determines whether the accuracies of the dual-RSM are high enough to replace the FEM computation. This strategy makes the FEM computation not always necessary at all the sample points in the optimization process and ensures the accuracy of the solution. For the purpose of showing the effectiveness of the proposed optimization methodology, the optimal design process of a dual PM-excited synchronous motor is taken as an example in this paper.
Autors: Liu, X.;Fu, W.N.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Fast Poisson Solver for 3-D Space Charge Calculations in a CPU+GPU Heterogeneous Routine
Abstract:
Space charge calculations play a key role in beam dynamics studies for particle accelerators and various other physical and technical fields. The major work is to solve Poisson’s equation for numerous time steps. Therefore, it is important to solve Poisson’s equation in a short time. In this paper, we present a CPU+GPU-based heterogeneous parallel computation routine with the compute unified device architecture platform in a normal PC. The new framework benefits from a novel efficient discrete cosine transform study using the classical Hockney and Eastwood’s convolution routine rather than the former one with discrete Fourier transform. A model problem has been studied, which showed an efficiency improvement with the new heterogeneous routine.
Autors: Zheng, D.;van Rienen, U.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Fault-Tolerant Dual Three-Level Inverter Configuration for Multipole Induction Motor Drive With Reduced Torque Ripple
Abstract:
Multilevel inverters are gaining more attention in ac drive application due to their many attractive features. In the case of conventional neutral-point-clamped (NPC) or flying capacitor multilevel inverter configurations, active switches are connected in series to produce multilevel output voltage waveform. Therefore, if any one switch fails, the entire configuration has to be shut down; this will reduce the reliability of the system. A dual three-level inverter configuration for induction motor drive is proposed in this paper to improve reliability of the system. This topology is developed by feeding four-pole induction motor stator winding with four conventional two-level inverter modules. A level-shifted carrier-based third harmonic injection pulsewidth-modulation technique is used to produce the gating signals for the proposed configuration. By providing proper phase shift between carrier waves, multilevel voltage waveform is produced across the total motor phase winding, and first center band harmonics are also canceled. Thereby, the torque ripple will be considerably reduced compared with conventional NPC five-level inverter-driven induction motor drive. Finite-element analysis (FEA) is used to estimate the torque ripple when induction motor is supplied by the proposed configuration and conventional five-level NPC inverter configuration to show the effectiveness of the proposed converter. The proposed configuration is simulated using MATLAB/Simulink and experimentally verified using a laboratory prototype with a 5-hp four-pole induction motor drive.
Autors: Nallamekala, K.K.;Sivakumar, K.;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Mar 2016, volume: 63, issue:3, pages: 1450 - 1457
Publisher: IEEE
 
» A Feedback Control Approach to Organic Drug Infusions Using Electrochemical Measurement
Abstract:
Goal: Target-controlled infusion of anesthesia is a closed-loop automated drug delivery method with a computer-aided control. Our goal is to design and test an automated drug infusion platform for propofol delivery in total intravenous anesthesia (TIVA) administration. Methods: In the proposed method, a dilution chamber with first-order exponential decay characteristics was used to model the pharmacodynamics decay of a drug. The dilution chamber was connected to a flow system through an electrochemical cell containing an organic film-coated glassy carbon electrode as working electrode. To set up the feedback-controlled delivery platform and optimize its parameters, ferrocene methanol was used as a proxy of the propofol. The output signal of the sensor was connected to a PI controller, which prompted a syringe pump for feedback-controlled drug infusion. Results: The result is a bench-top drug infusion platform to automate the delivery of a propofol based on the measurement of concentration with an organic film-coated voltammetric sensor. Conclusion: To evaluate the performance characteristics of the infusion platform, the propofol concentration in the dilution chamber was monitored with the organic film-coated glassy carbon electrode and the difference between the set and measured concentrations was assessed. The feasibility of measurement-based feedback-controlled propofol delivery is demonstrated and confirmed. Significance: This platform will contribute to high-performance TIVA application of intravenous propofol anesthesia.
Autors: Myers, M.H.;Li, Y.;Kivlehan, F.;Lindner, E.;Chaum, E.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Mar 2016, volume: 63, issue:3, pages: 506 - 511
Publisher: IEEE
 
» A Flexible Piezoelectric-Pyroelectric Hybrid Nanogenerator Based on P(VDF-TrFE) Nanowire Array
Abstract:
The piezoelectric and pyroelectric effects are well known and have been widely used for energy harvesting and self-powered sensing systems. This paper presents a high performance piezoelectric-pyroelectric hybrid nanogenerator based on P(VDF-TrFE) nanowire array that is capable of simultaneously harvesting mechanical and thermal energies. The nanowire array was synthesized by nanoimprinting P(VDF-TrFE) polymer into anodic aluminum oxide (AAO). The ferroelectric β crystalline phase of the aligned P(VDF-TrFE) nanowires has been demonstrated by Fourier transform infrared spectrum and X-ray diffraction measurements. Under periodic mechanical bending, electric signals are repeatedly generated from the hybrid nanogenerator and the measured piezoelectric output reach 4.0 V/65 nA. The cyclic bending–releasing process and impacts of strain rate on the electrical outputs are thoroughly characterized and analyzed. Besides, upon exposure of heat–cool condition with a temperature range of 8 K around room temperature, pyroelectric output up to 3.2 V/52 nA was obtained. There is a linear relationship between the output and the temperature difference across the device. Because the fast response time of 90 ms and high detected sensitivity of 0.8 K, the hybrid nanogenerator can also use as a self-powered temperature sensor. Finally, the piezoelectric and pyroelectric output voltages were successfully integrated together to obtain an enhanced output. These results demonstrate the great potential of the flexible hybrid nanogenerator for self-powered electronic devices.
Autors: Chen, X.;Shao, J.;Li, X.;Tian, H.;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Mar 2016, volume: 15, issue:2, pages: 295 - 302
Publisher: IEEE
 
» A Formal Model of QoS-Aware Web Service Orchestration Engine
Abstract:
QoS-aware applications can satisfy not only the functional requirements of the customers, but also the QoS requirements. QoS-aware Web service orchestration translates the QoS requirements of the customers into those of its component Web services. In a system viewpoint, we discuss issues on QoS-aware Web service orchestration and design a typical QoS-aware Web service orchestration engine called QoS-WSOE. More importantly, we establish a formal model of QoS-WSOE based on actor systems theory. Within the formal model, we use a three-layered pyramidal structure to capture the requirements of the customers with a concept named QoS-aware WSO service, characteristics of QoS-WSOE with a concept named QoS-aware WSO system, and structures and behaviors of QoS-WSOE with a concept named QoS-aware WSO behavior. Conclusions showing that a system with QoS-aware WSO behavior is a QoS-aware WSO system and further can provide QoS-aware WSO Service are drawn.
Autors: Wang, Y.;
Appeared in: IEEE Transactions on Network and Service Management
Publication date: Mar 2016, volume: 13, issue:1, pages: 113 - 125
Publisher: IEEE
 
» A Framework for Enabling User Preference Profiling through Wi-Fi Logs
Abstract:
Nowadays, mobile devices have become a ubiquitous medium supporting various forms of functionality and are widely accepted for commons. In this study, we investigate using Wi-Fi logs from a mobile device to discover user preferences. The core ideas are two folds. First, every Wi-Fi access point is with a network name, normally a human-readable string, called SSID (Service Set Identifier). Since SSIDs are often with semantics, from which we can infer the place where the user stayed. Second, a Wi-Fi log is produced when the user is near a Wi-Fi access point. A high frequency of a consecutively observed SSID implies a long stay duration at a place. To the best of our knowledge, our work is the first attempting to understand users from the collected Wi-Fi logs from mobile devices. However, Wi-Fi logs are essentially of various information types and with noises. How to assess the information types, eliminate irrelevant information, and clean up the noises within partial-informative SSIDs are therefore keys for profiling user preferences over Wi-Fi logs. In this paper, we propose a data cleaning and information enrichment framework for enabling the user preference understanding through collected Wi-Fi logs, and introduce a data clean framework for cleaning, correcting, and refining Wi-Fi logs. In addition, a comprehensive experiment with data collected from users is made to verify the effectiveness of the proposed techniques for cleaning noisy Wi-Fi data for user preferences profiling. The experiment results demonstrate the effectiveness of the proposed framework for profiling user preferences through Wi-Fi logs.
Autors: Fan, Y.;Chen, Y.;Tung, K.;Wu, K.;Chen, A.L.P.;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Mar 2016, volume: 28, issue:3, pages: 592 - 603
Publisher: IEEE
 
» A Frequency Reconfigurable Directive Antenna With Wideband Low-RCS Property
Abstract:
In this communication, a frequency reconfigurable directive antenna with low-radar cross section (RCS) property is presented. This antenna is composed of a slot-coupled microstrip patch and a two-layer metastructure. The top-layer metastructure integrates a partially reflection surface (PRS) with an absorbing surface, and the bottom-layer one consists of tunable reflection phase cells, which are loaded around the antenna source. The absorbing surface can absorb most of the incoming wave, and thus reduce the antenna RCS. The PRS and tunable reflection phase cells form a Fabry–Perot resonance cavity, making the antenna produce a highly directive beam. In addition, the operation frequency can be dynamically tuned by controlling the varactor diodes in the reflection phase cells. Both simulated and measured results have verified that employing the two-layer metastructure makes the antenna RCS largely reduced at a wide band ranging from 8 to 14 GHz. Compared with the traditional microstrip antenna, this antenna radiates a highly directive beam with gain enhancement of about 7 dB, and its operation frequency can be actively tuned from 9.05 to 10 GHz.
Autors: Huang, C.;Pan, W.;Ma, X.;Luo, X.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2016, volume: 64, issue:3, pages: 1173 - 1178
Publisher: IEEE
 
» A Fundamental Study of Applying Wind Turbines for Power System Frequency Control
Abstract:
As wind penetration increases in power systems around the world, new challenges to the controllability and operation of a power system are encountered. In particular, frequency response is impacted when a considerable amount of power-electronics interfaced generation, such as wind, is connected to the system. This paper uses small-signal analysis and dynamic simulation to study frequency response in power systems and investigate how Type-3 DFAG wind turbines can impact this response on a test power system, whose frequency response is determined mainly by a frequency-regulation mode. By operating the wind turbines in a deloaded mode, a proposed pitch-angle controller is designed using a root-locus analysis. Time simulations are used to demonstrate the transient and steady-state performance of the proposed controller in the test system with 25% and 50% wind penetration.
Autors: Wilches-Bernal, F.;Chow, J.H.;Sanchez-Gasca, J.J.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Mar 2016, volume: 31, issue:2, pages: 1496 - 1505
Publisher: IEEE
 
» A Fuzzy-Based Building Automation Control System: Optimizing the Level of Energy Performance and Comfort in an Office Space by Taking Advantage of Building Automation Systems and Solar Energy
Abstract:
Building automation systems (BASs) are the key to improving the energy performance of buildings as well as the occupants' comfort. There is a need to build a knowledge base on the matter and to grow suitable algorithms for a smart management of intelligent buildings. Therefore, fuzzy logic is a valuable candidate for developing robust algorithms. The scope of this article is to validate a fuzzy-logic approach with the ability to optimize the level of energy performance and comfort in an office space by taking advantage of BASs and solar energy. In BASs, dynamic elements, e.g., dynamic facade and luminaires, can exploit daylight and solar gain based on the condition that well-programmed integrated multicriteria decision-making methods are used. In this article, a virtual model of a smart office room (SOR) equipped with dynamic shading, lighting, and an air-conditioning control system was studied, and four different scenarios were considered: control versus no control, economy versus comfort mode, fluorescent versus light-emitting diode (LED), and dimming versus switching. Both economy and comfort mode showed a better energy performance than the noncontrolled scenarios. In conclusion, the proposed model is a valuable tool for optimizing comfort features and energy demand.
Autors: Martirano, L.;Parise, G.;Parise, L.;Manganelli, M.;
Appeared in: IEEE Industry Applications Magazine
Publication date: Mar 2016, volume: 22, issue:2, pages: 10 - 17
Publisher: IEEE
 
» A Game Theoretic Analysis of Secret and Reliable Communication With Active and Passive Adversarial Modes
Abstract:
Secret and reliable communication presents a challenge involving a double dilemma for a user and an adversary. One challenge for the adversary is to decide between jamming and eavesdropping. While jamming can be quite effective in preventing reliable communication of the user, it can also be quite harmful for the adversary since he/she can be detected. On the other hand, eavesdropping is quite safe for the adversary; however, it sometimes may not be so efficient compared to jamming, if the adversary cannot respond to the information gleaned from eavesdropping in a timely manner. The user can either transmit, thus becoming vulnerable to malicious activity, or be in a silent mode in turn delaying his/her transmission. However, by combining these modes properly the user can assist an intruder detection system in detecting the adversary, since transmission can provoke the adversary into a jamming attack, and a strategically allocated silent mode while the jammer continues jamming can increase the probability of detecting the adversary. In this paper, to get insight into this problem, two simple stochastic games are proposed. Explicit solutions are found that lead to the characterization of some interesting properties. In particular, it is shown that under certain conditions, incorporating in the transmission protocol a time slot dealing just with the detection of malicious threats can improve the secrecy and reliability of the communication without extra transmission delay.
Autors: Garnaev, A.;Baykal-Gursoy, M.;Poor, H.V.;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Mar 2016, volume: 15, issue:3, pages: 2155 - 2163
Publisher: IEEE
 
» A Game Theoretical Pricing Mechanism for Multi-Area Spinning Reserve Trading Considering Wind Power Uncertainty
Abstract:
The rapid development of wind power has led to an increased demand for spinning reserve in power systems today. However, one of the most severe challenges to China's power systems is the mismatch between wind power installation capacity and the capability for supplying spinning reserve within each independently operated provincial power system. Coordinating the spinning reserve across multiple areas would providentially improve the accommodation of wind power. This paper proposes a game-theoretical model for spinning reserve trading between provincial systems that treat spinning reserve as a commodity. Based on the incomplete information, the trading price is calculated by satisfying the Bayesian Nash equilibrium, and then the trading quantity is determined. This ensures that both the buyer and the seller are able to maximize their expected profit. Case studies are performed using a 2-bus interconnected system and a 3-area IEEE RTS system. The results show that the proposed model is valid and effective.
Autors: Xu, Q.;Zhang, N.;Kang, C.;Xia, Q.;He, D.;Liu, C.;Huang, Y.;Cheng, L.;Bai, J.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Mar 2016, volume: 31, issue:2, pages: 1084 - 1095
Publisher: IEEE
 
» A Generalized Domain-Decomposition Stochastic FDTD Technique for Complex Nanomaterial and Graphene Structures
Abstract:
The systematic and accurate design process of realistic nanocomposite applications and finite-sized graphene setups with arbitrary media uncertainties is presented in this paper by a 3-D covariant/contravariant stochastic finite-difference time-domain method. The new technique uses extra nodes pertinent to a convex combination of all obtainable spatial increments and introduces a robust domain-decomposition formulation combined with Lagrange multipliers to considerably decrease the system overhead. In this way, the mean value and the standard deviation of field components are evaluated in a single run. The performance of the proposed algorithm is validated by various statistically varying nanoscale applications.
Autors: Kantartzis, N.V.;Zygiridis, T.T.;Antonopoulos, C.S.;Kanai, Y.;Tsiboukis, T.D.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Generalized Methodology for Dynamic Average Modeling of High-Pulse-Count Rectifiers in Transient Simulation Programs
Abstract:
High-pulse-count rectifier systems (with more than six pulses) are often used in high-power applications. Dynamic average value modeling (AVM) has proven to be indispensable for simulation and analysis of such power electronic systems. However, developing accurate AVMs for such line-commutated converters is challenging due to the presence of complicated switching patterns (operating modes), configuration of multi-phase transformers and/or rotating machines, inter-phase transformers, filters, etc. This paper presents a generalized methodology for full-order dynamic average modeling of high-pulse-count line-commutated rectifiers, which is based on the recently proposed parametric AVM approach. Extensive simulation studies are carried out considering the 18-pulse rectifier example system. The accuracy and numerical advantages of the developed generalized AVM is verified against the detailed switching model, and a previously established average model in time and frequency domains.
Autors: Chiniforoosh, S.;Atighechi, H.;Jatskevich, J.;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Mar 2016, volume: 31, issue:1, pages: 228 - 239
Publisher: IEEE
 
» A Generalized Signature of Repairable Coherent Systems
Abstract:
We present a generalized signature in repairable coherent systems resembling Samaniego's notion for statistically independent and identically distributed lifetimes. The repairable systems are made of different components which can individually fail, and be minimally repaired up to a fixed number of times. Failures occur according to Poisson processes, which might have either the same intensity function for each component, or different ones. The former case is similar to the notion of signature presented by Samaniego for i.i.d. random variables, whereas here statistically independent Poisson processes with identical intensity functions are considered. An explicit expression for computing the generalized signature of repairable series systems is obtained. It is shown that the reliability function of any repairable coherent system can be expressed as a generalized mixture of the probabilities of the number of repairs until system failure. We also establish that the stochastic ordering between the generalized signatures of two repairable systems is preserved by their lifetimes.
Autors: Chahkandi, M.;Ruggeri, F.;Suarez-Llorens, A.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2016, volume: 65, issue:1, pages: 434 - 445
Publisher: IEEE
 
» A Generally Applicable Calibration Algorithm for Digitally Reconfigurable Self-Healing RFICs
Abstract:
A generally applicable calibration technique for digitally reconfigurable self-healing radio frequency integrated circuits based on a hybrid of the Nelder-Mead and Hooke-Jeeves direct search algorithms is presented. The proposed algorithm is applied to the multiobjective problem of gain error and phase error minimization for a self-healing phase rotator test case. For the 8-D phase rotator calibration problem, we show that the proposed hybrid Nelder-Mead and Hooke-Jeeves calibration algorithm is capable of reducing the gain error and phase error of the phase rotator output to less than a maximum of 0.5 dB and 2°, respectively, relative to the chosen gain and phase targets. A 3-GHz self-healing phase rotator test chip was fabricated in a 45-nm silicon-on-insulator CMOS process, and the measured data were obtained to validate the performance of the proposed calibration algorithm.
Autors: Wyers, E.J.;Morton, M.A.;Sollner, T.C.L.G.;Kelley, C.T.;Franzon, P.D.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2016, volume: 24, issue:3, pages: 1151 - 1164
Publisher: IEEE
 
» A Graph-Based Taxonomy of Recommendation Algorithms and Systems in LBSNs
Abstract:
Recently, location-based social networks (LBSNs) gave the opportunity to users to share geo-tagged information along with photos, videos, and SMSs. Recommender systems can exploit this geographic information to provide much more accurate and reliable recommendations to users. In this paper, we present and compare 16 real life LBSNs, bringing into surface their advantages/ disadvantages, their special functionalities, and their impact in the mobile social Web. Moreover, we describe and compare extensively 43 state-of-the-art recommendation algorithms for LBSNs. We categorize these algorithms according to: personalization type, recommendation type, data factors/features, problem modeling methodology, and data representation. In addition to the above categorizations which cannot cover all algorithms in an integrated way, we also propose a hybrid k-partite graph taxonomy to categorize them based on the number of the involved k-partite graphs. Finally, we compare the recommendation algorithms with respect to their evaluation methodology (i.e., datasets and metrics) and we highlight new perspectives for future work in LBSNs.
Autors: Kefalas, P.;Symeonidis, P.;Manolopoulos, Y.;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Mar 2016, volume: 28, issue:3, pages: 604 - 622
Publisher: IEEE
 
» A GTS Allocation Scheme to Improve Multiple-Access Performance in Vehicular Sensor Networks
Abstract:
The IEEE 802.15.4 protocol is designed to flexibly support both real-time and contention-based services. When the beacon model is enabled, guaranteed time slot (GTS) scheduling can provide contention-free access to latency-sensitive services based on the time-division multiple-access mechanism. This characteristic makes IEEE 802.15.4 the appropriate candidate for vehicular sensor networks in which mobile nodes need to exchange packets with roadside units (RSUs) within a limited duration. In this paper, using network calculus theory, we analyzed the relationship between time-slot utilization and the corresponding access parameters, such as packet arrival rate, burst size, and vehicles' mobility extent. Then, for a given number of vehicles preparing to access an RSU, we proposed a time-sensitive weighted round-robin (TS-WRR) scheduler to improve the multiple-access performance, which can take the service delay requirement, packet arrival rate, and vehicular mobility level into account. Next, the weight determination and time-slot allocation strategy of the TS-WRR scheduler were issued in detail, which incorporate the special limitations and application requirements in a vehicle-to-infrastructure (V2I) communication environment. To make our model feasible for testing, we also elaborately demonstrated the implementation procedure with pseudocode and simulator design. Numerical results show that our TS-WRR scheduler outperforms some classic schedulers such as First-Come First-Served and WRR, as well as two latest works, i.e., implicit GTS allocation scheme and adaptive real-time GTS allocation mechanism in terms of delay guarantee and GTS utilization maximization in vehicular sensor networks.
Autors: Chen, C.;Pei, Q.;Li, X.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Mar 2016, volume: 65, issue:3, pages: 1549 - 1563
Publisher: IEEE
 
» A Hierarchical Model for Lithium-Ion Battery Degradation Prediction
Abstract:
Developing prognostics and health management (PHM) approaches for lithium-ion batteries has received increasing attention in recent years. This paper presents a new modeling framework to characterize lithium-ion battery degradation by examining detailed discharging voltage profiles in different discharging cycles. We propose a hierarchical model, combining discharging processes and degradation processes, to predict the end of discharges in different cycles and remaining useful cycles integratively. We use a real case study to demonstrate the effectiveness and promising features of the proposed framework.
Autors: Xu, X.;Li, Z.;Chen, N.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2016, volume: 65, issue:1, pages: 310 - 325
Publisher: IEEE
 
» A High-Performance Pathway: A 0.95/2.45-GHz Switched-Fequency Bandpass Filter Using Commercially Available RF MEMS Tuning Elements
Abstract:
Software-defined radio chip sets are becoming increasingly available for a wide variety of RF bands including the industrial, scientific, and medical (ISM) bands. Efficient operation of systems like these typically requires high-performance, multifunctional RF filters to enable preselection of the signals of interest while suppressing undesired interferers and noise. To fulfill these requirements and ensure high-quality transmission of the desired signal within a range of ISM bands using a single compact signal path, miniaturized and highly selective bandpass filters (BPFs) with broadband switching/tuning capabilities need to be developed.
Autors: Hickle, M.;Li, J.;Psychogiou, D.;Peroulis, D.;
Appeared in: IEEE Microwave Magazine
Publication date: Mar 2016, volume: 17, issue:3, pages: 34 - 41
Publisher: IEEE
 
» A High-Throughput Hardware Design of a One-Dimensional SPIHT Algorithm
Abstract:
Video display systems include frame memory, which stores video data for display. To reduce system cost, video data are often compressed for storage in frame memory. A desirable characteristic for display memory compression is support for the raster-scan processing order and the fixed target compression ratio. Set partitioning in hierarchical trees (SPIHT) is an efficient two-dimensional compression algorithm that guarantees a fixed target compression ratio, but its one-dimensional (1D) variation has received little attention, even though its 1D nature supports the raster-scan processing order. This paper proposes a novel hardware design for 1D SPIHT. The algorithm is modified to exploit parallelism for effective hardware implementation. For the encoder, dependences that prohibit parallel execution are resolved and a pipelined schedule is proposed. For the parallel execution of the decoder, the algorithm is modified to enable estimation of the bitstream length of each pass prior to decoding. This modification allows parallel and pipelined decoding operations, leading to a high-throughput design for both encoder and decoder. Although the modifications slightly decrease compression efficiency, additional optimizations are proposed to improve such efficiency. As a result, the peak signal-to-noise ratio drop is reduced from 1.40 dB to 0.44 dB. The throughputs of the proposed encoder and decoder are 7.04 Gbps and 7.63 Gbps, respectively, and their respective gate counts are 37.2 K and 54.1 K.
Autors: Kim, S.;Lee, D.;Kim, J.;Lee, H.;
Appeared in: IEEE Transactions on Multimedia
Publication date: Mar 2016, volume: 18, issue:3, pages: 392 - 404
Publisher: IEEE
 
» A Hybrid Double-Threshold Based Cooperative Spectrum Sensing over Fading Channels
Abstract:
This paper investigates double-threshold-based energy detector for cooperative spectrum sensing mechanisms in cognitive wireless radio networks. We first propose a hybrid double-threshold-based energy detector (HDTED) to improve the sensing performance at secondary users (SUs) by exploiting both the local binary/energy decisions and global binary decisions feedback from the fusion center (FC). Significantly, we derive closed-form expressions and bounds for the probabilities of missed detection and false alarm considering a practical scenario where all channel links suffer from Rayleigh fading and background noise. The derived expressions not only show the improved performance achieved with the HDTED scheme but also enable us to analyze the impacts of the number of the SUs and the fading channels on the cooperative spectrum sensing performance. Furthermore, based on the derived bounds, we propose an optimal SU selection algorithm for forwarding the local decisions to the FC, which helps reduce the number of forwarding bits for a lower-complexity signaling. Finally, numerical results are provided to demonstrate the validity of the analytical findings.
Autors: Vien, Q.;Nguyen, H.;Trestian, R.;Shah, P.;Gemikonakli, O.;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Mar 2016, volume: 15, issue:3, pages: 1821 - 1834
Publisher: IEEE
 
» A Hybrid FEM/MoM Technique for 3-D Electromagnetic Scattering From a Dielectric Object Above a Conductive Rough Surface
Abstract:
A hybrid approach combining the edge-based vector finite-element method (FEM) and the method of moments (MoM) is first extended to study 3-D scattering from a dielectric object above a conductive rough surface. The hybrid FEM/MoM technique is based on the electric field vector Helmholtz's equation. To reduce the calculational domain, the solution region is divided into the FEM region containing the object and the MoM region containing the rough surface. In our hybrid method, tetrahedral elements are applied to handle the object region based on vector basis functions, whereas triangular elements are used to deal with the rough surface based on Rao–Wilton–Glisson basis functions. The electromagnetic coupling between the object and the rough surface is considered by the surface integral equation with the Green's function. The hybrid technique presented here combines advantages between FEM and MoM, which is highly efficient in terms of computing memory, time consumed, and versatility.
Autors: Xu, R.;Guo, L.;He, H.;Liu, W.;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Mar 2016, volume: 13, issue:3, pages: 314 - 318
Publisher: IEEE
 
» A Hybrid Quantitative Method for Inverse Scattering of Multiple Dielectric Objects
Abstract:
A hybrid method is proposed to locate the boundaries and determine the dielectric constants of multiple homogeneous scatterers by postprocessing the results of the linear sampling method (LSM). The hybrid method is composed of three steps combining the capabilities of the LSM, the multiple signal classification (MUSIC) algorithm, and the generalized multipole technique (GMT). Initially, a new measure of the noise level of the multistatic response (MSR) matrix is proposed. Subsequently, the LSM is applied using the Tikhonov regularization. Then, the scattered field is back-propagated into the investigation domain using the GMT, where in order to ensure the stability, a MUSIC-based approach is exploited to determine the optimum reconstructing multipole sources. The case of limited scattered field data is also addressed by introducing a modification of the Papoulis–Gerchberg algorithm (PGA). Finally, the boundary and the dielectric constant of each scatterer are obtained simultaneously by solving an inverse boundary value problem through an optimization. The proposed hybrid approach is capable of efficiently approximating the dielectric constant of multiple homogeneous dielectric scatterers in a parallel manner. The effectiveness of the proposed method and the accuracy of the solutions are demonstrated by applying the method to both numerical and measured data.
Autors: Rabbani, M.;Tavakoli, A.;Dehmollaian, M.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2016, volume: 64, issue:3, pages: 977 - 987
Publisher: IEEE
 
» A Hybridized Vector Optimal Algorithm for Multi-Objective Optimal Designs of Electromagnetic Devices
Abstract:
Multiple-objective designs exist in most real-world engineering problems in different disciplines. A multi-objective evolutionary algorithm will face a challenge to obtain a series of compromises of different objectives, called Pareto optimal solutions, and to distribute them uniformly. In this regard, it is essential to keep the balance of local and global search abilities of such algorithms. Quantum-behaved particle swarm optimization (QPSO) is a population-based swarm intelligence algorithm, and differential evolutionary (DE) is another simple population-based stochastic search one for global optimization with real-valued parameters. Although the two optimizers have been successfully employed to solve a wide range of design problems, they also suffer from premature convergence and insufficient diversity in the later searching stages. This is probably due to the insufficient dimensional searching strength, especially for problems with many decision parameters. In this paper, a new multi-objective non-dominated optimal methodology combining QPSO, DE, and tabu search algorithm (QPSO-DET) is proposed to guarantee the balance between the local and global searches. The performances of the proposed QPSO-DET are compared with those of other two widely recognized vector optimizers using different case studies.
Autors: Hu, G.;Yang, S.;Li, Y.;Khan, S.U.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Mar 2016, volume: 52, issue:3, pages: 1 - 4
Publisher: IEEE
 
» A Joint Antenna and Path Selection Technique in Single-Relay-Based DF Cooperative MIMO Networks
Abstract:
In this paper, we consider a single-relay-based decode-and-forward (DF) cooperative multiple-input multiple-output (MIMO) system in which the source, the relay, and the destination are equipped with , , and antennas, respectively. We propose a joint antenna and path selection scheme, which jointly selects the single-transmit and single-receive antenna pairs, along with the selection of either a direct path that consists of source–destination channels or a cooperative path that consists of source–relay and relay–destination channels. The proposed selection scheme is based on the maximization of minimum of maximums (max-min-max) criterion of instantaneous signal-to-noise ratio (SNR). The analysis in this paper is based on the assumptions that all the channels follow independent Rayleigh fading. A closed-form expression of the symbol error rate (SER) for the proposed scheme in a cooperative MIMO system with -ary phase-shift keying is derived. We extract the analytical diversity order from the derived SER and show that the proposed selection scheme achieves the diversity order of in the considered cooperative MIMO system. Closed-form expressions of bandwidth efficiency (BE) and ergodic capacity are derived for the proposed scheme. An optimized selection parameter from the specific set of values is numerically evaluated by maximizing a heuristic utility function . By using the already-gathered information about the maximum instantaneous SNR of every hop, a power adaptation scheme that maximizes the instantaneous SNR in the cooperative path is proposed and analyzed. The proposed power adaptation scheme, which is applied only in the event of selection of a cooperative path, outperforms the uniform-power-distribution-based DF cooperative MIMO system.
Autors: Sai Krishna, V.;Bhatnagar, M.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Mar 2016, volume: 65, issue:3, pages: 1340 - 1353
Publisher: IEEE
 
» A Joint Cross-Layer and Colayer Interference Management Scheme in Hyperdense Heterogeneous Networks Using Mean-Field Game Theory
Abstract:
In hyperdense heterogeneous networks (HetNets), efficient intercell interference management is an important issue. In this paper, using recent advances in mean-field game (MFG) theory, we propose a novel game-theoretic approach for interference management in HetNets. The intercell interference management issue in HetNets is formulated as two nested problems: an overlay problem at the macrocell base station (MBS) level and an underlay problem at the small-cell base station (SBS) level. In the overlay problem, the MBS selects the optimal action first, which satisfies its associated users with a minimum amount of cross-layer interference, taking into account the reaction of the SBSs. The underlay problem is then formulated as a noncooperative game among the SBSs. The mean-field theory is exploited to help decouple a complex large-scale optimization problem into a family of localized optimization problems. Thus, each SBS can implement its policy by using only its local information and some macroscopic information. In addition to the achieved tradeoff between spectral efficiency (SE) and energy efficiency (EE), our approach can substantially reduce the communication overhead and convergence time of interference management in hyperdense HetNets. Simulation results are presented to show the effectiveness of the proposed scheme.
Autors: Al-Zahrani, A.;Yu, F.;Huang, M.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Mar 2016, volume: 65, issue:3, pages: 1522 - 1535
Publisher: IEEE
 
» A Joint Time Synchronization and Localization Design for Mobile Underwater Sensor Networks
Abstract:
Time synchronization and localization are basic services in a sensor network system. Although they often depend on each other, they are usually tackled independently. In this work, we investigate the time synchronization and localization problems in underwater sensor networks, where more challenges are introduced because of the unique characteristics of the water environment. These challenges include long propagation delay and transmission delay, low bandwidth, energy constraint, mobility, etc. We propose a joint solution for localization and time synchronization, in which the stratification effect of underwater medium is considered, so that the bias in the range estimates caused by assuming sound waves travel in straight lines in water environments is compensated. By combining time synchronization and localization, the accuracy of both are improved jointly. Additionally, an advanced tracking algorithm interactive multiple model (IMM) is adopted to improve the accuracy of localization in the mobile case. Furthermore, by combining both services, the number of required exchanged messages is significantly reduced, which saves on energy consumption. Simulation results show that both services are improved and benefit from this scheme.
Autors: Liu, J.;Wang, Z.;Cui, J.;Zhou, S.;Yang, B.;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Mar 2016, volume: 15, issue:3, pages: 530 - 543
Publisher: IEEE
 

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