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Electrical and Electronics Engineering publications abstract of: 03-2015 sorted by title, page: 0
» "There Is No Saturation Point in Education": Inside IBM's Sales School, 1970s-1980s
Abstract:
The author was both a student and an instructor in IBM's training program for newly hired salespeople in the 1970s and 1980s. He describes the training these new hires received, focusing on Sales School, IBM's longest running training program.
Autors: Cortada, James W.;
Appeared in: IEEE Annals of the History of Computing
Publication date: Mar 2015, volume: 37, issue:1, pages: 56 - 66
Publisher: IEEE
 
» 1.5-kW Yb-Raman Combined Nonlinear Fiber Amplifier at 1120 nm
Abstract:
A high power Yb-Raman combined nonlinear fiber amplifier employing dual-wavelength seed is demonstrated. The amplifier is seeded by 1070- and 1120-nm signal lasers simultaneously. The mechanism of power evolution of the two signals along the gain fiber is analyzed. By careful design and optimization of the amplifier, we make sure the 1120-nm signal extract majority of the gain in the amplifier. In the end, 1.52-kW 1120-nm laser is obtained with an optical efficiency of 75.6%, which is the highest power ever reported near this wavelength. The compact and efficient amplifier scheme proposed in this letter can be employed for high power amplification of 1100–1200-nm lasers.
Autors: Zhang, H.;Tao, R.;Zhou, P.;Wang, X.;Xu, X.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Mar 2015, volume: 27, issue:6, pages: 628 - 630
Publisher: IEEE
 
» 1/ Noise Characteristics of Surface-Treated Normally-Off Al2O3/GaN MOSFETs
Abstract:
Normally off Al2O3/GaN MOSFETs are fabricated with a tetramethylammonium hydroxide (TMAH) treatment as a postgate recess etch. The effects of the surface treatment on the etched GaN surface are investigated using low-frequency (1/ ) noise and capacitance–voltage ( – ) measurements. For a quantitative comparison with conventional devices, the oxide trap density ( ) is extracted using the unified 1/ noise model, whereas the interface trap density ( ) is extracted using the high–low-frequency – method. After the TMAH treatment, is found to have decreased from to 2.50 , whereas is decreased from 2.8 to $1.1 times 10^{mathrm {mathbf {11}}}~mathrm{eV}^{mathrm {mathbf {-1}}}$ , as compared with conventional devices. The surface treatment is thus shown to lower trap density in the Al2O3/GaN MOSFETs by smoothing the surface and suppressing plasma damage in the recessed GaN surfaces.
Autors: Sakong, S.;Lee, S.;Rim, T.;Jo, Y.;Lee, J.;Jeong, Y.;
Appeared in: IEEE Electron Device Letters
Publication date: Mar 2015, volume: 36, issue:3, pages: 229 - 231
Publisher: IEEE
 
» 2.5D Cartoon Hair Modeling and Manipulation
Abstract:
This paper addresses a challenging single-view modeling and animation problem with cartoon images. Our goal is to model the hairs in a given cartoon image with consistent layering and occlusion, so that we can produce various visual effects from just a single image. We propose a novel 2.5D modeling approach to deal with this problem. Given an input image, we first segment the hairs of the cartoon character into regions of hair strands. Then, we apply our novel layering metric, which is derived from the Gestalt psychology, to automatically optimize the depth ordering among the hair strands. After that, we employ our hair completion method to fill the occluded part of each hair strand, and create a 2.5D model of the cartoon hair. By using this model, we can produce various visual effects, e.g., we develop a simplified fluid simulation model to produce wind blowing animations with the 2.5D hairs. To further demonstrate the applicability and versatility of our method, we compare our results with real cartoon hair animations, and also apply our model to produce a wide variety of hair manipulation effects, including hair editing and hair braiding.
Autors: Chih-Kuo Yeh;Jayaraman, P.K.;Xiaopei Liu;Chi-Wing Fu;Tong-Yee Lee;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Mar 2015, volume: 21, issue:3, pages: 304 - 314
Publisher: IEEE
 
» 3-D FEM Calculation of Electromagnetic Properties of Single-Phase Induction Machines
Abstract:
In comparison with three-phase induction machines, modern single-phase induction machines normally have skewed rotors, but show an elliptic magnetic field during start-up. In order to properly model the start-up of such a machine, this three-dimensional (3-D) characteristic has to be accounted for. This leads to the application of the 3-D finite-element method. This paper will introduce a new approach to model and analyze the start-up of such a single-phase machine, with the aim of higher computational efficiency. Furthermore, this paper will discuss how symmetries, both in the circumferential direction and along the motor shaft, can be exploited despite the skewing. This is achieved through transforming (rotating) the cutting plane, doubling the skewing angle, and increasing the rotor conductor conductivity. The analysis is carried out on a small two-pole 100-W machine used for household appliances. The theoretical results are compared with experimental results for six rotors; each with a different skewing angle.
Autors: Bacher, J.;Waldhart, F.;Muetze, A.;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Mar 2015, volume: 30, issue:1, pages: 142 - 149
Publisher: IEEE
 
» 3-D High-Resolution Imaging Radar at 300 GHz With Enhanced FoV
Abstract:
We have developed a 3-D high-resolution radar at 300 GHz with a cell resolution of at a standoff distance of 8 m for security applications. The selection of an operating frequency of 300 GHz, a bandwidth of 27 GHz, and a field of view of improves the through-clothes imaging of person-borne concealed objects. The radar's antenna design allows single-pixel imaging at a frame rate of two frames per second. A reduction in cost and power consumption and improvements in image quality are additional requirements taken into account in the design of this radar system.
Autors: Grajal, J.;Badolato, A.;Rubio-Cidre, G.;Ubeda-Medina, L.;Mencia-Oliva, B.;Garcia-Pino, A.;Gonzalez-Valdes, B.;Rubinos, O.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1097 - 1107
Publisher: IEEE
 
» 3-D Printed All-Dielectric Frequency Selective Surface With Large Bandwidth and Field of View
Abstract:
In this paper, an all-dielectric frequency selective surface (ADFSS) was developed using genetic algorithms and fast Fourier transforms (FFTs) to generate random geometries. This device showed a stop-band fractional bandwidth (FBW) of 54% and a field of view of 16°. The optimized FSS was manufactured by three-dimensional (3-D) printing and the frequency response was measured in the laboratory. This device was also tested in the pass band at a high pulsed microwave power of and no damage was observed. This is the first known demonstration of a 3-D printed ADFSS.
Autors: Barton, J.H.;Garcia, C.R.;Berry, E.A.;Salas, R.;Rumpf, R.C.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2015, volume: 63, issue:3, pages: 1032 - 1039
Publisher: IEEE
 
» 310-W Single Frequency Tm-Doped All-Fiber MOPA
Abstract:
We present a high-power single frequency (SF) Tm-doped fiber amplifier employing all-fiber master oscillator power amplifier (MOPA) configuration. An SF fiber laser with ultrashort cavity and output power of mW was used as the seed laser of the MOPA, and the central wavelength located at nm. The final output power of the MOPA reaches 310 W with slope efficiency of 0.56, and no amplified spontaneous emission or parasitic lasing is observed. The stimulated Brillouin scattering threshold is not reached yet, and the output power is only pump limited. This is the first demonstration, to the best of our knowledge, on an SF Tm-doped all-fiber MOPA with output power exceeding 300 W.
Autors: Wang, X.;Jin, X.;Wu, W.;Zhou, P.;Wang, X.;Xiao, H.;Liu, Z.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Mar 2015, volume: 27, issue:6, pages: 677 - 680
Publisher: IEEE
 
» 3D channel model in 3GPP
Abstract:
Multi-antenna techniques capable of exploiting the elevation dimension are anticipated to be an important air-interface enhancement targeted to handle the expected growth in mobile traffic. In order to enable the development and evaluation of such multi-antenna techniques, the 3rd Generation Partnership Project (3GPP) has recently developed a three-dimensional (3D) channel model. The existing two-dimensional (2D) channel models do not capture the elevation channel characteristics, making them insufficient for such studies. This article describes the main components of the newly developed 3D channel model and the motivations behind introducing them. One key factor is the ability to model channels for users located on different floors of a building (at different heights). This is achieved by capturing a user height dependency in modelling some channel characteristics including pathloss, lineof- sight (LOS) probability, etc. In general, this 3D channel model follows the framework of WINNERII/WINNER+ while also extending the applicability and the accuracy of the model by introducing some height dependent and distance dependent elevation related parameters.
Autors: Mondal, B.;Thomas, T.A.;Visotsky, E.;Vook, F.W.;Ghosh, A.;Young-Han Nam;Yang Li;Jianzhong Zhang;Min Zhang;Qinglin Luo;Kakishima, Y.;Kitao, K.;
Appeared in: IEEE Communications Magazine
Publication date: Mar 2015, volume: 53, issue:3, pages: 16 - 23
Publisher: IEEE
 
» 3D Visual Servoing Control for Robot Manipulators Without Parametric Identification
Abstract:
Visual servoing control of robot manipulators represents a natural option in unstructured environments and it is specially attractive when the task to achieve can be expressed directly in image coordinates. In the present work a control law is developed for trajectory tracking of three degrees of freedom robot manipulators. The main characteristic of the proposed algorithm is that it does not need any dynamic model of the system and image coordinates are employed directly for feedback, while an observer is designed for velocity estimation. To carry out 3D movements no stereoscopic vision is used. Rather, a simpler configuration employing two fixed cameras is proposed which makes unnecessary their calibration and helps avoid occlusions for most of the robots workspace. The developed theory was successfully tested in an industrial manipulator.
Autors: Arteaga Perez, Marco Antonio;Bueno Lopez, Maximiliano;
Appeared in: IEEE Latin America Transactions
Publication date: Mar 2015, volume: 13, issue:3, pages: 569 - 577
Publisher: IEEE
 
» 5G Communications Race: Pursuit of More Capacity Triggers LTE in Unlicensed Band
Abstract:
Fifth-generation (5G) network developers need to identify the necessary requirements toward additional capacity and spectrally efficient wireless technologies. Therefore, the significant amount of underutilized spectrum in the Wi-Fi band is motivating operators to combine long-term evolution (LTE) with Wi-Fi technologies. This new LTE in unlicensed band (LTE-U) has the physical layer topology to access Wi-Fi spectrum, specifically the 5-GHz band. Nevertheless, the evolution of LTE-U affects the Wi-Fi operations due to the absence of any regularity for LTE-U transmissions in unlicensed band. In this article, we address the challenges for Wi-Fi to maintain transmissions under the umbrella of LTE-U as Wi-Fi is pushed offline because of the listen-before-talk (LBT) feature. Therefore, we derive a new adaptive LBT mechanism and and virtualized core network for the best practices in both Wi-Fi and LTE-U technologies. The proposed solutions include noncoordinated and coordinated network managements to enable coexistence between both technologies using tradeoff performance for fair spectrum sharing. We concentrate on the initial coexistent technique and discuss how it maps to higher-layer improvements. This article shows new approaches to achieve the Third-Generation Partnership Project (3GPP) Release 13.
Autors: Al-Dulaimi, A.;Al-Rubaye, S.;Ni, Q.;Sousa, E.;
Appeared in: IEEE Vehicular Technology Magazine
Publication date: Mar 2015, volume: 10, issue:1, pages: 43 - 51
Publisher: IEEE
 
» 60-GHz Substrate Integrated Waveguide Fed Cavity-Backed Aperture-Coupled Microstrip Patch Antenna Arrays
Abstract:
Cavity-backed patch antenna arrays with full corporate substrate integrated waveguide (SIW) feed networks are demonstrated at V-band for applications with the needs of high-gain antennas. A prototype of radiating elements with a waveguide transition is fabricated by applying standard printed circuit board (PCB) facilities. A gain up to 30.1 dBi with a 3-dB gain bandwidth of 16.1%, an impedance bandwidth of 15.3% for , and symmetrically broadside radiation patterns with cross-polarizations are achieved. The performance of the proposed antenna array is also systematically evaluated. The result serves as a reference for designing large antenna arrays operating at millimeter-wave frequencies.
Autors: Li, Y.;Luk, K.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2015, volume: 63, issue:3, pages: 1075 - 1085
Publisher: IEEE
 
» 60-GHz Substrate Materials Characterization Using the Covered Transmission-Line Method
Abstract:
At millimeter-wave (mm-wave) frequencies, antennas and systems are highly influenced by the electromagnetic characteristics of packaging materials. Accurate knowledge of the complex permittivity of packaging materials is vital for the optimal and robust design of such systems. In this paper, the covered transmission-line method is used to determine the complex permittivity at 60 GHz for several common FR-4 and FR-5 packaging materials. Measurements show that packaging materials must be accurately characterized at high frequencies because their properties can appreciably differ from those at lower frequencies. Moreover, depending on the fabrication process, different thickness samples of the same material can have different permittivity values. The complex permittivity variation versus temperature is also analyzed. We show that, at low frequencies, this variation is negligible, but at mm-wave frequencies, it can represent up to a 5% variation in the relative permittivity and have a severe impact on the loss tangent. The covered transmission-line method is explained in detail and its accuracy and measurable permittivity range are also discussed.
Autors: Papio Toda, A.;De Flaviis, F.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1063 - 1075
Publisher: IEEE
 
» 802.11 WLAN: history and new enabling MIMO techniques for next generation standards
Abstract:
IEEE 802.11, which designs wireless local area networks (WLAN), is one of the most successful standards in wireless communication systems. In this article, we review the history of WLAN standards, and provide technical overviews of the recent development of WLAN systems. Especially, as the original inventor and the proposer, we focus on beamforming and compressed feedback schemes, which have been adopted in 802.11 WLAN standards, to improve the throughput for a multiple-input multiple-output (MIMO) system. These techniques are essential to maximize the downlink system throughput for multiple user transmission as well as for single user transmission. Also, we present discussions on new technologies to further enhance user throughput, which are currently considered for future WLAN systems.
Autors: Kim, J.;Lee, I.;
Appeared in: IEEE Communications Magazine
Publication date: Mar 2015, volume: 53, issue:3, pages: 134 - 140
Publisher: IEEE
 
» -Consecutive- , -Out-of- Systems
Abstract:
Here we present the structure functions for the linear and circular -consecutive- , -out-of- :F (G) systems, which consists of linearly or circularly ordered components such that the system fails (works) iff there are at least times -overlapping runs of consecutive failed (working) components. The duality of these F and G systems is obtained, and the proofs are given. The generalized reliability formulae for the systems are obtained by using the finite Markov chain imbedding approach for statistically independent and Markov-dependent cases. Some miscellaneous results on the reliability of these systems and numerical examples are provided to illustrate the results obtained in the paper.
Autors: Cui, L.;Lin, C.;Du, S.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2015, volume: 64, issue:1, pages: 386 - 393
Publisher: IEEE
 
» -Consecutive- , -Out-of- Systems
Abstract:
Here we present the structure functions for the linear and circular -consecutive- , -out-of- :F (G) systems, which consists of linearly or circularly ordered components such that the system fails (works) iff there are at least times -overlapping runs of consecutive failed (working) components. The duality of these F and G systems is obtained, and the proofs are given. The generalized reliability formulae for the systems are obtained by using the finite Markov chain imbedding approach for statistically independent and Markov-dependent cases. Some miscellaneous results on the reliability of these systems and numerical examples are provided to illustrate the results obtained in the paper.
Autors: Cui, L.;Lin, C.;Du, S.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2015, volume: 64, issue:1, pages: 386 - 393
Publisher: IEEE
 
» -Gain Analysis for Positive Linear Systems With Unbounded Time-Varying Delays
Abstract:
This technical note addresses the -gain (respectively, -gain) analysis problem for discrete-time (respectively, continuous-time) positive linear systems with unbounded time-varying delays. For the discrete-time case, by virtue of the monotonicity of an auxiliary system and the corresponding delay-free system, it is shown that the -gain of discrete-time positive systems with unbounded delays is insensitive of the magnitude of delays. For the continuous-time case, we first construct a sampled-data positive system and analyze its monotonicity and asymptotic behavior. Then, by comparing the delayed positive system with the proposed sampled-data positive system and the corresponding delay-free system, it is further proved that the -gain of continuous-time positive systems with unbounded delays is also independent of the delays and fully determined by the system matrices. The application of the results is illustrated by a sampled-data system with unbounded sampling intervals.
Autors: Shen, J.;Lam, J.;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Mar 2015, volume: 60, issue:3, pages: 857 - 862
Publisher: IEEE
 
» -Gain Analysis for Positive Linear Systems With Unbounded Time-Varying Delays
Abstract:
This technical note addresses the ℓ-gain (respectively, L-gain) analysis problem for discrete-time (respectively, continuous-time) positive linear systems with unbounded time-varying delays. For the discrete-time case, by virtue of the monotonicity of an auxiliary system and the corresponding delay-free system, it is shown that the ℓ-gain of discrete-time positive systems with unbounded delays is insensitive of the magnitude of delays. For the continuous-time case, we first construct a sampled-data positive system and analyze its monotonicity and asymptotic behavior. Then, by comparing the delayed positive system with the proposed sampled-data positive system and the corresponding delay-free system, it is further proved that the L-gain of continuous-time positive systems with unbounded delays is also independent of the delays and fully determined by the system matrices. The application of the results is illustrated by a sampled-data system with unbounded sampling intervals.
Autors: Jun Shen;Lam, J.;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Mar 2015, volume: 60, issue:3, pages: 857 - 862
Publisher: IEEE
 
» Recognition of 2014 Transactions and Magazine Papers Reviewer
Abstract:
Lists the reviewers who contribute to IEEE Industry Applications Magazine and the IEEE Transactions on Industry Applications in 2014.
Autors: Speck, C.E.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1117 - 1131
Publisher: IEEE
 
» In Vivo and In Vitro Comparison of the Charge Injection Capacity of Platinum Macroelectrodes
Abstract:
Platinum (Pt) is the most commonly used metal for stimulating electrodes. This study aims to determine the amount of charge that can be delivered without causing irreversible electrochemical reactions (charge injection capacity, Q inj) of Pt macroelectrodes (geometric surface area >0.001 cm2) in vitro and in vivo using voltage transient measurements. Pt macroelectrodes were stimulated with biphasic charge-balanced cathodic-first constant-current pulses in phosphate buffered saline. Potential excursions were measured (versus Ag/AgCl electrode) and used to determine Qinj. The in vitro Qinj were compared to those measured in vivo following: acute and chronic implantation close to the retina; chronic intracochlear implantation; and acute subdural implantation, in the cat. Qinj increased with pulsewidth from 35 to 54 μC/cm2 for respective pulse widths of 100 to 3200 μs per phase in vitro. Qinj was significantly less in vivo. There was no significant difference in Qinj between acutely (3.84 to 16.6 μC/cm2 with pulsewidths of 100 to 3200 μs) and chronically (6.99 to 15.8 μC/cm2 with pulsewidths of 200 to 3200 μs) implanted suprachoroidal electrodes. Intracochlear Qinj was not different to suprachoroidal Qinj, while subdural Qinj was significantly less than the suprachoroidal Q inj (p < 0.05). These results have important implications in providing guidelines on Qinj for the safe use of Pt stimulating macroelectrodes and question the relevance of measuring Qinj in vivo using voltage transients.
Autors: Leung, R.T.;Shivdasani, M.N.;Nayagam, D.A.X.;Shepherd, R.K.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Mar 2015, volume: 62, issue:3, pages: 849 - 857
Publisher: IEEE
 
» A 0.0045- 32.4- Two-Stage Amplifier for pF-to-nF Load Using CM Frequency Compensation
Abstract:
This brief reports an embedded capacitor multiplier (CM) frequency compensation technique to realize an extremely compact micropower two-stage amplifier for wide capacitive load ( ) drivability. It features: 1) a valuable left half-plane zero to enhance the closed-loop stability over a wide range of ; 2) no extra bias circuit and power, as the CM is embedded into the first stage of the amplifier, and 3) only one very small (subpicofarad) compensation capacitor improving the transient settling and area efficiency. Detailed analytical treatments of the amplifier offer the critical insights for device sizing and optimization. Fabricated in 0.18- CMOS, the amplifier measures 3.06-MHz unity-gain frequency (UGF), 1.76- average slew rate (SR), and phase margin (PM) at 20-pF , and 0.22-MHz UGF, 0.049- SR, and PM at 15-nF . The die size is 0.0045 , and power is at 1.2 V. Competitive large- and small-signal figures of merit are achieved with respect to the state of the art.
Autors: Yan, Z.;Wang, W.;Mak, P.;Law, M.;Martins, R.P.;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Mar 2015, volume: 62, issue:3, pages: 246 - 250
Publisher: IEEE
 
» A 0.0045- 32.4- Two-Stage Amplifier for pF-to-nF Load Using CM Frequency Compensation
Abstract:
This brief reports an embedded capacitor multiplier (CM) frequency compensation technique to realize an extremely compact micropower two-stage amplifier for wide capacitive load ( ) drivability. It features: 1) a valuable left half-plane zero to enhance the closed-loop stability over a wide range of ; 2) no extra bias circuit and power, as the CM is embedded into the first stage of the amplifier, and 3) only one very small (subpicofarad) compensation capacitor improving the transient settling and area efficiency. Detailed analytical treatments of the amplifier offer the critical insights for device sizing and optimization. Fabricated in 0.18- CMOS, the amplifier measures 3.06-MHz unity-gain frequency (UGF), 1.76- average slew rate (SR), and phase margin (PM) at 20-pF , and 0.22-MHz UGF, 0.049- SR, and PM at 15-nF . The die size is 0.0045 , and power is at 1.2 V. Competitive large- and small-signal figures of merit are achieved with respect to the state of the art.
Autors: Yan, Z.;Wang, W.;Mak, P.;Law, M.;Martins, R.P.;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Mar 2015, volume: 62, issue:3, pages: 246 - 250
Publisher: IEEE
 
» A 0.33 V 683 K-Band Transformer-Based Receiver Front-End in 65 nm CMOS Technology
Abstract:
An ultra-low-power transformer-based K-band receiver front-end is implemented in a 65 nm CMOS technology. For noise and input matching, a gate-to-source transformer-feedback technique is applied to the first-stage of the LNA. A transformer-based gain-boosting feedback technique is adopted in the second-stage of the LNA for further gain enhancement without additional dc power. Several transformers are utilized for inter-stage matching of the LNA and for single-to-differential LO/RF baluns of the ring mixer. By using forward-body-bias technique, the LNA operates at 0.33 V supply. For low-power receiver, a resistive ring mixer is adopted. The receiver demonstrates a 12.5 dB conversion gain (CG) and a 5.7 dB double-side band NF at IF frequency of 100 MHz with LO power of -10 dBm while consuming only 683 . To the best of our knowledge, the receiver demonstrates the lowest dc power consumption among recently reported K-band CMOS receiver.
Autors: Cheng, J.-H.;Hsieh, C.-L.;Wu, M.-H.;Tsai, J.-H.;Huang, T.-W.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Mar 2015, volume: 25, issue:3, pages: 184 - 186
Publisher: IEEE
 
» A 1.2-V 4.2- High-Order Curvature-Compensated CMOS Bandgap Reference
Abstract:
This study presents a high-precision CMOS bandgap reference (BGR) circuit with low supply voltage. The proposed BGR circuit consists of two BGR cores and a curvature correction circuit, which includes a current mirror and a summing circuit. Two BGR cores adopt conventional structures with the curvature-down characteristics. A current-mirror circuit is proposed to implement one of the BGR cores to have the curvature-up characteristic. Selection of the appropriate resistances in the BGR cores results in one reference voltage with a well balanced curvature-down characteristic and another reference voltage with an evenly balanced curvature-up characteristic. The summation of these reference voltages is proposed to achieve a high-order curvature compensation. This curvature correction circuit causes the proposed BGR circuit without any trimming to show a measured temperature coefficient (TC) as low as 4.2 ppm/°C over a wide temperature range of 160 °C (-40 ~ 120 °C) at a power supply voltage of 1.2 V. The average TC for 8 random samples is approximately 9.3 ppm/°C. The measured power-supply rejection ratio (PSRR) of -30 dB is achieved at the frequency of 100 kHz. The total chip size is 0.063 mm2 with a standard 0.13-μm CMOS process.
Autors: Quanzhen Duan;Jeongjin Roh;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 662 - 670
Publisher: IEEE
 
» A 1.2-V 4.2- High-Order Curvature-Compensated CMOS Bandgap Reference
Abstract:
This study presents a high-precision CMOS bandgap reference (BGR) circuit with low supply voltage. The proposed BGR circuit consists of two BGR cores and a curvature correction circuit, which includes a current mirror and a summing circuit. Two BGR cores adopt conventional structures with the curvature-down characteristics. A current-mirror circuit is proposed to implement one of the BGR cores to have the curvature-up characteristic. Selection of the appropriate resistances in the BGR cores results in one reference voltage with a well balanced curvature-down characteristic and another reference voltage with an evenly balanced curvature-up characteristic. The summation of these reference voltages is proposed to achieve a high-order curvature compensation. This curvature correction circuit causes the proposed BGR circuit without any trimming to show a measured temperature coefficient (TC) as low as 4.2 over a wide temperature range of 160 at a power supply voltage of 1.2 V. The average TC for 8 random samples is approximately 9.3 . The measured power-supply rejection ratio (PSRR) of 30 dB is achieved at the frequency of 100 kHz. The total chip size is 0.063 with a standard 0.13- CMOS process.
Autors: Duan, Q.;Roh, J.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 662 - 670
Publisher: IEEE
 
» A 1.9 GHz CMOS High Isolation Absorptive OOK Modulator
Abstract:
This letter presents a high-isolation absorptive 1.9 GHz on-off keying (OOK) modulator in 90 nm CMOS process. The RF leakage-canceling technique is developed to suppress the RF leakage by combining it with its inverse replica at the output. The transform-typed baluns are used for the input and output matching such that the modulator input and output return losses change only slightly between the on and off states. The measured off-isolation of the CMOS OOK modulator is higher than 39.2 dB and the modulator has the on-state signal gain of 3.6 dB.
Autors: Ling, C.-C.;Yang, H.-S.;Chen, J.-H.;Chen, Y.-J.E.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Mar 2015, volume: 25, issue:3, pages: 190 - 192
Publisher: IEEE
 
» A 10-Gb/s, 1.24 pJ/bit, Burst-Mode Clock and Data Recovery With Jitter Suppression
Abstract:
A burst mode clock and data recovery (BMCDR) circuit for 10 Gbps passive optical network (10G-PON) is presented. The proposed BMCDR is reconfigurable between data gating mode and phase tracking mode to achieve instantaneously phase-locked with jitter suppression capability. Incorporating selectively gating VCO (SGVCO), the BMCDR operates at 1/5-rate and accomplishes 1:5 demultiplexing with a high energy efficiency of 1.24 pJ/bit. With a 4 MHz, jitter stressed input data at 10 Gbps, the recovered clock jitter at 2 GHz is 2.94 . The prototype is fabricated using 55 nm CMOS technology. The core area is 0.03 only. It dissipates 12.4 mW from 1 V supply.
Autors: Su, M.-C.;Chen, W.-Z.;Wu, P.-S.;Chen, Y.-H.;Lee, C.-C.;Jou, S.-J.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 743 - 751
Publisher: IEEE
 
» A 13.3 mW 500 Mb/s IR-UWB Transceiver With Link Margin Enhancement Technique for Meter-Range Communications
Abstract:
This paper describes a link margin enhancement method for high data rate impulse-radio ultra-wideband (IR-UWB) transceiver systems. To overcome a trade-off between link margin and spectrum compliance in the pulse based UWB system, a spectrum-efficient frequency hopping (FH) technique is proposed to increase average transmission power without violating the spectrum mask. An energy detection receiver is used to convert a frequency hopping signal to a baseband signal with the original bandwidth, thus improving the signal-to-noise ratio. A 500 Mb/s 7.25–9.5 GHz UWB transceiver is implemented in 65 nm CMOS. Having eight sub-bands with 50% overlap, the transceiver exhibits a meter-range communication capability with a 9 dB link margin enhancement. The transceiver consumes 13.3 mW from a 1 V supply, achieving an energy efficiency of 26.6 pJ/bit.
Autors: Geng, S.;Liu, D.;Li, Y.;Zhuo, H.;Rhee, W.;Wang, Z.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2015, volume: 50, issue:3, pages: 669 - 678
Publisher: IEEE
 
» A 16-mW 8-Bit 1-GS/s Digital-Subranging ADC in 55-nm CMOS
Abstract:
This paper presents a digital-subranging (sub-R) analog-to-digital conversion (ADC) architecture to improve the operation speed of sub-R ADCs. Long latency between coarse and fine conversions will slow down the conventional sub-R ADCs. The proposed digital-sub-R uses digital circuits to implement the sub-R function and shorten this latency, thus benefits the CMOS scaling. Furthermore, the dynamic comparators are used to save more ADC power consumption. Their accuracy is improved by the proposed pseudodifferential offset calibration loop. The digital-sub-R also helps to reduce the dynamic offset of the fine comparators caused by the input common-mode variation. Fabricated using a 55-nm CMOS technology, the reported 8-bit 1-GS/s ADC consumes only 16 mW from a 1.2 V supply. Measured signal-to-noise ratio (SNR) and spurious free dynamic range (SFDR) are 46 and 55 dB, respectively. Measured effective number of bits (ENOB) is seven bits at 10-MHz input frequency. At Nyquist input, the ENOB performance of 6.3 bits is still maintained. Its figure-of-merit is 197-fJ/conversion-step.
Autors: Chung, Y.;Wu, J.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2015, volume: 23, issue:3, pages: 557 - 566
Publisher: IEEE
 
» A 2.88 mW 9.06 dBm IIP3 Common-Gate LNA With Dual Cross-Coupled Capacitive Feedback
Abstract:
A CMOS common-gate low noise amplifier (LNA) with dual cross coupled capacitive feedback is proposed. The first feedback loop is designed for transcoductance boosting which is widely known as the cross-coupled common gate (CCCG) topology. The other feedback loop is voltage-current feedback by cross-coupling between the drain node and the source node in the common gate topology. In particular, the first feedback loop is able to reduce the amplification of a second-order signal while it boosts the transconductance of a fundamental signal thus, it can reduce the second order harmonic feedback effect to the input-referred third-order intercept point (IIP3) which is one of the major bottlenecks of linearity enhancement using feedback. As the first feedback removes second-order harmonic distortion, the second feedback successfully enhances IIP3. The proposed LNA achieves excellent performance with low power consumption. The LNA is implemented with a 0.13 CMOS process and measured. The measurement results demonstrate a gain of 18 dB, a noise figure (NF) of 1.94 dB, an IIP3 of 9.06 dBm, an input matching (S11)/output matching (S22) of less than 10 dB at 900 MHz, and a power consumption of 2.4 mA with 1.2 V supply voltage.
Autors: Han, H.G.;Jung, D.H.;Kim, T.W.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1019 - 1025
Publisher: IEEE
 
» A 2.88 mW 9.06 dBm IIP3 Common-Gate LNA With Dual Cross-Coupled Capacitive Feedback
Abstract:
A CMOS common-gate low noise amplifier (LNA) with dual cross coupled capacitive feedback is proposed. The first feedback loop is designed for transcoductance boosting which is widely known as the cross-coupled common gate (CCCG) topology. The other feedback loop is voltage-current feedback by cross-coupling between the drain node and the source node in the common gate topology. In particular, the first feedback loop is able to reduce the amplification of a second-order signal while it boosts the transconductance of a fundamental signal thus, it can reduce the second order harmonic feedback effect to the input-referred third-order intercept point (IIP3) which is one of the major bottlenecks of linearity enhancement using feedback. As the first feedback removes second-order harmonic distortion, the second feedback successfully enhances IIP3. The proposed LNA achieves excellent performance with low power consumption. The LNA is implemented with a 0.13 CMOS process and measured. The measurement results demonstrate a gain of 18 dB, a noise figure (NF) of 1.94 dB, an IIP3 of 9.06 dBm, an input matching (S11)/output matching (S22) of less than 10 dB at 900 MHz, and a power consumption of 2.4 mA with 1.2 V supply voltage.
Autors: Han, H.G.;Jung, D.H.;Kim, T.W.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1019 - 1025
Publisher: IEEE
 
» A 3-D Large Signal Model for Sheet Beam Traveling Wave Tubes
Abstract:
A 3-D frequency domain large signal code called sheet beam traveling-wave tube 3-D (SBTWT3-D) for illustrating the nonlinear beam–wave interaction in the SBTWT is presented in this paper. A recent published field theory model for illustrating the staggered double-grating arrays waveguide (SDGAW) slow-wave structure is adopted in the code to obtain the RF circuit fields’ distribution and ohmic loss. The sheet beam is simulated by a set of discrete rays. The ac and dc space-charge fields are obtained by solving the discrete Helmholtz equations and the discrete Poisson equation, respectively. A 3-D nonlinear beam–wave interaction analysis for a W-band SDGAW SBTWT is performed and the calculation results are compared with those obtained from time-domain 3-D particle-in-cell simulations.
Autors: Xie, W.;Wang, Z.;Luo, J.;Zhao, D.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2015, volume: 62, issue:3, pages: 1010 - 1016
Publisher: IEEE
 
» A 3.6-mW 50-MHz PN Code Acquisition Filter via Statistical Error Compensation in 180-nm CMOS
Abstract:
In this brief, we present a novel architecture for pseudorandom (PN) code acquisition based on statistical error compensation (SEC), which achieves significant power savings. SEC treats errors in hardware as noise in communication networks, and employs robust estimation theory to compensate for errors. We apply SEC to a 256-tap PN code acquisition filter in a 180- nm CMOS process. Multiple (five) dies were tested under voltage overscaling to achieve a near constant detection probability above 90%. The minimum energy consumption ranged from 72.89 to 210.59 pJ (ave 122.52 pJ) for supply voltages between 0.69 and 0.70 V. These operating conditions result in raw error rates of 85.83%–91.23% (ave 88.99%). Energy savings over a conventional error-free design ranges from to (ave ). Energy savings over past work ranges from to (ave ). Improvement in error-tolerance over existing error-tolerant designs range from to (ave ). The large energy savings were found to be due to a combination of voltage scaling and activity factor reduction. The proposed design achieves a
Autors: Kim, E.P.;Baker, D.J.;Narayanan, S.;Shanbhag, N.R.;Jones, D.L.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2015, volume: 23, issue:3, pages: 598 - 602
Publisher: IEEE
 
» A 32–48 Gb/s Serializing Transmitter Using Multiphase Serialization in 65 nm CMOS Technology
Abstract:
A power-efficient transmitter is proposed using a multiphase serializer, multiphase dividers using injection-locked oscillators, and a high-speed multiplexing structure to relax the timing constraints. With this architecture, bit times near 1 FO-4 gate delay are achieved using only nominal devices in a 65 nm CMOS technology. The divider and serializer operate over a wide range of data rates between 32 and 48 Gb/s limited mainly by the operation range of the frequency synthesizer. The transmitter occupies 0.4 mm and consumes 88 mW from a 1.2 V supply which corresponds to 1.8 pJ/bit of power efficiency.
Autors: Hafez, A.A.;Chen, M.-S.;Yang, C.-K.K.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2015, volume: 50, issue:3, pages: 763 - 775
Publisher: IEEE
 
» A 40-nm CMOS, 1.1-V, 101-dB Dynamic-Range, 1.7-mW Continuous-Time ADC for a Digital Closed-Loop Class-D Amplifier
Abstract:
This paper presents a continuous-time third-order modulator designed for closing the feedback loop of a digital class-D audio amplifier. The closed-loop digital class-D amplifier fully exploits the potential of the used 40-nm CMOS technology to achieve at the same time the flexibility of digital implementations and the performance of analog solutions. The proposed modulator consumes 1.7 mW from a 1.1-V power supply, achieving 101-dB dynamic-range and 72-dB peak signal-to-noise and distortion ratio . The active-RC implementation allows the 1.1-V modulator inputs to be directly connected to the 5-V class-D amplifier power stage outputs and inherently guarantees third-order anti-aliasing filtering.
Autors: Donida, A.;Cellier, R.;Nagari, A.;Malcovati, P.;Baschirotto, A.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 645 - 653
Publisher: IEEE
 
» A 42 fJ/Step-FoM Two-Step VCO-Based Delta-Sigma ADC in 40 nm CMOS
Abstract:
A 40 MHz-BW 10 bit two-step VCO-based Delta-Sigma ADC is presented. With the open-loop structure and highly digital building blocks, a robust performance, high bandwidth and high power efficiency are achieved. The nonlinearities of the coarse and the fine VCO-based quantizers are mitigated by distortion cancellation and voltage swing reduction schemes respectively. Because of the intrinsic DEM of the VCO-based quantizer output, the matching requirement of the DAC cells is greatly relaxed. The experimental results in 40 nm CMOS show that, with 1.6 GHz sampling frequency, the proposed ADC reaches 59.5 dB SNDR and 67.7 dB SFDR for 40 MHz bandwidth. The power consumption is only 2.57 mW under 0.9 V power supply, corresponding the best FoM (42 fJ/step) among high bandwidth ( 20 MHz) DS ADCs.
Autors: Xing, X.;Gielen, G.G.E.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2015, volume: 50, issue:3, pages: 714 - 723
Publisher: IEEE
 
» A 6-to-10-Bit 0.5 V-to-0.9 V Reconfigurable 2 MS/s Power Scalable SAR ADC in 0.18 CMOS
Abstract:
An asynchronous successive approximation register (SAR) analog-to-digital converter (ADC) for sensor applications is presented. High linear and power efficient switching scheme is proposed. The proposed low leakage latched dynamic cell in SAR logic and wide range configurable delay element extend the flexibility of speed and resolution tradeoff. The ADC fabricated in 0.18 μm CMOS process covers 6-10 bit resolution and 0.5 V-0.9 V power supply range. At 10 bit mode and 0.5 V operation, the proposed SAR ADC achieves 56.36 dB SNDR and 67.96 dB SFDR with sampling rate up to 2 MS/s, corresponding to a figure-of-merit of 20.6 fJ/conversion-step. The proposed ADC core occupies an active area of about 300×700 μm2.
Autors: Zhangming Zhu;Zheng Qiu;Maliang Liu;Ruixue Ding;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 689 - 696
Publisher: IEEE
 
» A 60 V Tolerance Transceiver With ESD Protection for FlexRay-Based Communication Systems
Abstract:
In this paper, a 60 V tolerance transceiver with ESD (electrostatic discharge) protection is proposed for FlexRay-based communication systems. The FlexRay transceiver comprises three protective devices, including an over-voltage detector, high-voltage ESD devices, and high-voltage diodes. The over-voltage detector is in charge of detecting bus (BP and BM) status to distinguish whether any hazard has happened. If the over-voltage detector is activated, the FlexRay transceiver must be turned off for safety. The high-voltage ESD device uses a base-floating PNP serving as a bi-directional device. Besides, it can protect the FlexRay transceiver whenever it is short-circuited in positive or negative high voltages. Notably, the high-voltage diode will eliminate the negative leakage current when negative high voltage hazards appear in FlexRay channels. An experimental prototype is implemented using a 0.18 CMOS mixed-signal based generation II HV BCD process. The measurement results justify the functional correctness and 60 V tolerance of the proposed FlexRay transceiver design.
Autors: Wang, C.-C.;Chen, C.-L.;Hou, Z.-Y.;Hu, Y.;Lee, J.-W.;Lin, W.-Y.;Chang, Y.-F.;Hsu, C.-W.;Song, M.-H.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 752 - 760
Publisher: IEEE
 
» A 71-Gb/s NRZ Modulated 850-nm VCSEL-Based Optical Link
Abstract:
We report error free ( ) operation of a directly non-return-to-zero modulated 850-nm vertical cavity surface-emitting laser (VCSEL) link operating to 71 Gb/s. This is the highest error free modulation rate for a directly modulated laser of any type. The optical link consists of a 130-nm BiCMOS driver IC with two-tap feed-forward equalization, a wide bandwidth 850-nm VCSEL, a surface illuminated GaAs PIN photodiode, and a 130-nm BiCMOS receiver IC.
Autors: Kuchta, D.M.;Rylyakov, A.V.;Doany, F.E.;Schow, C.L.;Proesel, J.E.;Baks, C.W.;Westbergh, P.;Gustavsson, J.S.;Larsson, A.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Mar 2015, volume: 27, issue:6, pages: 577 - 580
Publisher: IEEE
 
» A 94 GHz 3D Image Radar Engine With 4TX/4RX Beamforming Scan Technique in 65 nm CMOS Technology
Abstract:
This paper presents a fully-integrated 3D image radar engine utilizing beamforming for electrical scanning and precise ranging technique for distance measurement. Four transmitters and four receivers form a sensor frontend with phase shifters and power combiners adjusting the beam direction. A built-in 31.3 GHz clock source and a frequency tripler provide both RF carrier and counting clocks for the distance measurement. Flip-chip technique with low-temperature co-fired ceramic (LTCC) antenna design creates a miniature module as small as 6.5 4.4 0.8 cm . Designed and fabricated in 65 nm CMOS technology, the transceiver array chip dissipates 960 mW from a 1.2-V supply and occupies chip area of 3.6 2.1 mm . This prototype achieves scanning range, 2-m maximum distance, and 1 mm depth resolution.
Autors: Peng, P.-J.;Chen, P.-N.;Kao, C.;Chen, Y.-L.;Lee, J.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2015, volume: 50, issue:3, pages: 656 - 668
Publisher: IEEE
 
» A Balun-Free Helical Antenna for Minimally Invasive Microwave Ablation
Abstract:
We present a balun-free coax-fed helical antenna for microwave ablation. The proposed antenna produces a localized specific absorption rate pattern at the desired frequency of operation without using a coaxial balun. This reduces the outer diameter of the antenna and, thus, its invasiveness. Balun-free operation of the proposed antenna is achieved by operating the helical antenna at the second resonant frequency of the helix where a current minimum occurs at the feed point, resulting in an intrinsically high feed-point impedance. This efficiently chokes the currents excited on the outer surface of the feeding cable. Using a compact quarter-wavelength impedance transformer or a coaxially implemented pi network of reactive elements at the antenna feed point, we achieve an excellent impedance match between the antenna and the main feeding line. We fabricated a prototype of the proposed helical antenna with an outer diameter of 2.2 mm using the pi matching network. We used this prototype to conduct ablation experiments in ex vivo bovine liver. The dimensions of the resulting ablation zones are similar to those produced by coaxially fed antennas that use coaxial baluns. Our balun-free antenna design offers a promising solution for reducing the invasiveness of interstitial antennas used in microwave ablation.
Autors: Luyen, H.;Hagness, S.C.;Behdad, N.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2015, volume: 63, issue:3, pages: 959 - 965
Publisher: IEEE
 
» A Bayesian Model for Complex System Reliability Growth Under Arbitrary Corrective Actions
Abstract:
This paper presents a new method for projecting the reliability growth of a complex continuously operating system. The model allows for arbitrary corrective action strategies, and it differs from other models of this type by using all available data rather than failure mode first occurrence times only. It also differs from other reliability growth projection models in that it provides a complete inference framework via the posterior distribution on the system failure intensity. A unique feature of this approach relative to other Bayesian techniques is the analytic expression for the failure intensity contribution from unobserved failure modes. Expressions for estimating the initial failure intensity, growth potential failure intensity, and the cumulative number of failure modes expected in future testing are also developed. Extensions to the basic framework are also developed. The first accounts for multiple systems under test, and the second develops the posterior distribution while allowing for uncertainty on the Fix Effectiveness Factor values that are assessed. Two separate goodness-of-fit procedures are presented for assessing the appropriateness of the underlying model assumptions.
Autors: Wayne, M.;Modarres, M.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2015, volume: 64, issue:1, pages: 206 - 220
Publisher: IEEE
 
» A Bayesian Predictive Model for Clustering Data of Mixed Discrete and Continuous Type
Abstract:
Advantages of model-based clustering methods over heuristic alternatives have been widely demonstrated in the literature. Most model-based clustering algorithms assume that the data are either discrete or continuous, possibly allowing both types to be present in separate features. In this paper, we introduce a model-based approach for clustering feature vectors of mixed type, allowing each feature to simultaneously take on both categorical and real values. Such data may be encountered, for instance, in chemical and biological analyses, in the analysis of survey data, as well as in image analysis. Our model is formulated within a Bayesian predictive framework, where clustering solutions correspond to random partitions of the data. Using conjugate analysis, the posterior probability for each possible partition can be determined analytically, enabling the utilization of efficient computational search strategies for finding the posterior optimal partition. The derived model is illustrated using several synthetic and real datasets.
Autors: Blomstedt, P.;Jing Tang;Jie Xiong;Granlund, C.;Corander, J.;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Mar 2015, volume: 37, issue:3, pages: 489 - 498
Publisher: IEEE
 
» A Black-Box Approach to Detect Vulnerabilities in Web Services Using Penetration Testing
Abstract:
Web services work over dynamic connections among distributed systems. This technology was specifically designed to easily pass SOAP message through firewalls using open ports. These benefits involve a number of security challenges, such as Injection Attacks, phishing, Denial-of-Services (DoS) attacks, and so on. The difficulty to detect vulnerabilities,before they are exploited, encourages developers to use security testing like penetration testing to reduce the potential attacks. Given a black-box approach, this research use the penetration testing to emulate a series of attacks, such as Cross-site Scripting (XSS), Fuzzing Scan, Invalid Types, Malformed XML, SQL Injection, XPath Injection and XML Bomb. In this way, was used the soapUI vulnerability scanner in order to emulate these attacks and insert malicious scripts in the requests of the web services tested. Furthermore, was developed a set of rules to analyze the responses in order to reduce false positives and negatives. The results suggest that 97.1% of web services have at least one vulnerability of these attacks. We also determined a ranking of these attacks against web services.
Autors: Palma Salas, Marcelo Invert;Martins, Eliane;
Appeared in: IEEE Latin America Transactions
Publication date: Mar 2015, volume: 13, issue:3, pages: 707 - 712
Publisher: IEEE
 
» A Blocker-Tolerant Current Mode 60-GHz Receiver With 7.5-GHz Bandwidth and 3.8-dB Minimum NF in 65-nm CMOS
Abstract:
A current-mode 60-GHz direct-conversion receiver, which can break performance tradeoffs among bandwidth, noise figure (NF), and linearity is designed and realized in 65-nm CMOS. The 60-GHz receiver employs the novel frequency-staggered series resonance common source (FSRCS) stage to extend RF bandwidth with superior noise performance. The receiver's current-mode operation offers excellent out-of-band blocker tolerance and linearity. With on-chip quadrature local oscillator generations, the fabricated receiver simultaneously achieves minimal NF of 3.8 dB, RF bandwidth of 7.5 GHz, output of 1 dBm, and maximum conversion gain of 36 dB. The receiver is capable of tolerating out-of-channel blocker up to 9 dBm at 3.5 GHz away. It occupies a silicon area of 1.3 and draws 25.5 mA of current from a 1-V supply.
Autors: Wu, H.;Wang, N.-Y.;Du, Y.;Chang, M.-C.F.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1053 - 1062
Publisher: IEEE
 
» A Boosting Pass Gate With Improved Switching Characteristics and No Overdriving for Programmable Routing Switch Based on Crystalline In-Ga-Zn-O Technology
Abstract:
A boosting pass gate (BPG) suitable for a programmable routing switch including a -axis aligned crystal In-Ga-Zn-O (CAAC-IGZO) field effect transistor (FET) is proposed. The CAAC-IGZO is one of crystalline oxide semiconductors (OS). The proposed BPG (OS-based BPG, OS BPG) has a combination of a pass gate (PG) and a configuration memory (CM) cell utilizing a CAAC-IGZO FET with extremely low OFF-state current and a storage capacitor. This OS BPG achieves a routing switch with fewer transistors than a conventional routing switch having a combination of a PG and an static RAM (SRAM) cell. Owing to the boosting effect, the switching characteristics, at not only positive transition but also negative transition of input signals, of the OS BPG are improved without using overdriving. In circuits fabricated with a hybrid process of a CMOSFET and a CAAC-IGZO FET with gate lengths of 0.5 and 1.0 m, the net delays of the OS BPG, 75 and 58 ns, at driving voltages of 2.0 and 2.5 V have been found to be less than those of the conventional routing switch (SRAM-based PG, SRAM PG) by about 79% and 62%, respectively. It has also been confirmed that a field-programmable gate array (FPGA) chip utilizing the OS BPG as a routing switch reduces the layout areas of routing switches and the whole chip by 61% and 22%, respectively, and increases the maximum operating frequencies at driving voltage of 2.0 and 2.5 V by about 2.8 times and 1.6 times of those of the FPGA chip utilizing the SRAM PG as a routing switch.
Autors: Okamoto, Y.;Nakagawa, T.;Aoki, T.;Ikeda, M.;Kozuma, M.;Osada, T.;Kurokawa, Y.;Ikeda, T.;Yamade, N.;Okazaki, Y.;Miyairi, H.;Fujita, M.;Koyama, J.;Yamazaki, S.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2015, volume: 23, issue:3, pages: 422 - 434
Publisher: IEEE
 
» A Burst-Mode Digital Receiver With Programmable Input Jitter Filtering for Energy Proportional Links
Abstract:
A full-rate burst-mode receiver that achieves fast on/off operation needed for energy-proportional links is presented. By injecting input data edges into the oscillator embedded in a classical Type-II digital clock and data recovery (CDR) circuit, the proposed receiver achieves instantaneous phase-locking and input jitter filtering simultaneously. In other words, the proposed CDR combines the advantages of conventional feed-forward and feedback architectures to achieve energy-proportional operation. By controlling the number of data edges injected into the oscillator, both the jitter transfer bandwidth and the jitter tolerance corner are accurately controlled. The feedback loop also corrects for any frequency error and helps improve CDR's immunity to oscillator frequency drift during the power-on and -off states. This also improves CDR's tolerance to consecutive identical digits present in the input data. Fabricated in a 90 nm CMOS process, the prototype receiver instantaneously locks onto the very first data edge and consumes 6.1 mW at 2.2 Gb/s. Owing to its short power-on time, the receiver's energy efficiency varies only from 2.77 pJ/bit to 3.87 pJ/bit when the effective data rate is varied from 0.44 Gb/s to 2.2 Gb/s. Input sensitivity of the receiver is 36 mV for a BER of 10 .
Autors: Choi, W.-S.;Anand, T.;Shu, G.;Elshazly, A.;Hanumolu, P.K.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Mar 2015, volume: 50, issue:3, pages: 737 - 748
Publisher: IEEE
 
» A Centralized PSD Map Construction by Distributed Compressive Sensing
Abstract:
In the context of spectrum reusing in Cognitive Radio (CR) networks, spectrum availability should be considered with respect to both space and frequency in making the Power Spectral Density (PSD) map concept. For this reason, the sensed PSDs by the distributed sensors in the area are collected and fused by a fusion center (FC). But, for a given zone, the sensed PSD by neighbor CR sensors may contain a shared common component for a while, and this component can be exploited in the theory of the distributed source coding to compress as much as possible. For this reason, distributed compressive sensing (DCS) methods are used here to exploit the correlation between PSDs and compress them more and reduce this type of overhead traffic. The proposed method can be used to develop a framework when the holding time of the users is large in comparison with the rate of the spectrum sensing.
Autors: Eslami, M.;Torkamani-Azar, F.;Mehrshahi, E.;
Appeared in: IEEE Communications Letters
Publication date: Mar 2015, volume: 19, issue:3, pages: 355 - 358
Publisher: IEEE
 
» A Channel Allocation Algorithm for Reducing the Channel Sensing/Reserving Asymmetry in 802.11ac Networks
Abstract:
The major goal of IEEE 802.11ac is to provide very high throughput (VHT) performance while at the same time guaranteeing backward compatibility. To achieve this goal, 802.11ac adopts the channel bonding technique that makes use of multiple 20 MHz channels in 5 GHz band. Due to the heterogeneity of bandwidth that each device exploits, and the fixed total transmission power in the standards, a problem called ‘Hidden Channel’ arises. In this paper, we first analyze the problem and show how the contention parameters and transmission time affect collision probability and fairness in some deployment scenarios. Then, we propose a heuristic channel allocation algorithm that aims to avoid such problematic situations effectively. Through simulations, we demonstrate that our proposed channel allocation algorithm lowers the packet error rate (PER) compared to uncoordinated and received signal strength indicator(RSSI) based allocation schemes and increases the network-wide throughput as well as the throughput of a station that experiences poor performance. This implies improved fairness performance among transmission pairs with various channel bandwidths.
Autors: Jang, S.;Bahk, S.;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Mar 2015, volume: 14, issue:3, pages: 458 - 472
Publisher: IEEE
 
» A Class of Quasi-Switched Boost Inverters
Abstract:
A switched boost inverter (SBI) can replace a -source inverter (ZSI) in low-power applications because it has one less pair than the ZSI. This paper presents a class of quasi-SBIs (qSBIs) that offers several advantages when compared with a conventional SBI, including reducing the voltage stress on the capacitor, increasing the boost voltage factor, and improving input current profiles. Operating principles, steady-state analysis, and comparisons with conventional inverters are presented. A prototype based on a TMS320F28335 digital signal processor is built to verify the operating principle of the proposed qSBIs.
Autors: Nguyen, M.;Le, T.;Park, S.;Lim, Y.;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Mar 2015, volume: 62, issue:3, pages: 1526 - 1536
Publisher: IEEE
 
» A Compact Analytical Model for the Drain Current of Gate-All-Around Nanowire Tunnel FET Accurate From Sub-Threshold to ON-State
Abstract:
We present a compact analytical model for the drain current of a gate-all-around nanowire tunneling field effect transistor. The model takes into account the effect of oxide thickness, body doping, drain voltage, and gate metal work function. The model uses a tangent line approximation method to integrate the tunneling generation rate in the source-body depletion region. The accuracy of the model is tested against three dimensional numerical simulations calibrated using experimental results. The model predicts the drain current accurately in both the on-state (strong inversion), as well as in the sub-threshold region.
Autors: Vishnoi, R.;Kumar, M.J.;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Mar 2015, volume: 14, issue:2, pages: 358 - 362
Publisher: IEEE
 
» A Compact Planar Printed MIMO Antenna Design
Abstract:
In this paper, we describe the design of a novel planar multiple-input-multiple-output (MIMO) antenna. The basic idea of the design is the development of a canonical two-port antenna that can be replicated and concatenated together to form MIMO antennas with arbitrary even numbers of ports. The design of the canonical element uses compact folded slots for the radiating elements but includes the use of field cancelation to enhance isolation by incorporating a coupling parasitic element. In addition by properly designing the coupling parasitic and the two-port antenna, coupling between canonical elements is also reduced allowing them to be concatenated together. The canonical element size is operating at 2.6 GHz and it can be packed together with high densities of up to 22 elements per square wavelength. To validate the design, results from 20-port planar printed MIMO antennas are presented operating at 2.6 GHz with a bandwidth of 100 MHz. The 20-port antenna has size of providing an antenna density of 22 antenna in free space square wavelength ( ). Even though the individual antennas are densely packed, all combinations of mutual couplings between ports exhibit better than 10 dB isolation. The antennas are printed on an FR-4 printed circuit board (PCB), which is a low-cost substrate and allows straightforward prototyping.
Autors: Soltani, S.;Murch, R.D.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Mar 2015, volume: 63, issue:3, pages: 1140 - 1149
Publisher: IEEE
 
» A Compact Tunable Notch Filter With Wide Constant Absolute Bandwidth
Abstract:
A compact notch filter with a wide tunable frequency range is developed. This tunable filter is composed of two varactor-tuned resonators, shunted at input/output ports separately, and one quarter-wavelength transmission line connecting two varactor-tuned resonators. By enlarging impedance of the quarter-wavelength transmission line, the proposed tunable filter can obtain a wide and constant absolute bandwidth within the whole tunable frequency band. The measured results show that there is a wide tuning range, 124.3%. In addition, with insertion loss greater than 20 dB, a wide constant absolute bandwidth can be achieved at 450 MHz.
Autors: Tang, C.-W.;Chen, W.-C.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Mar 2015, volume: 25, issue:3, pages: 151 - 153
Publisher: IEEE
 
» A Comparative Analysis of Phase-Domain ADC and Amplitude-Domain IQ ADC
Abstract:
A phase-domain analog-to-digital converter (PhADC) is a promising alternative to a pair of amplitude-domain in-phase and quadrature (IQ) ADCs for low power FSK/PSK demodulation, but the fundamental benefits and limitations of the PhADC over the IQ ADC have not been precisely quantified as yet. In this paper, analytical methods are proposed to comprehensively compare the PhADC and the IQ ADC. Phase signal-to-noise ratio (SNR) expressions of the two ADC types are formulated analytically to facilitate a quantitative comparison of them. In comparison with the IQ ADC, the PhADC is a more compact quantization and demodulation solution when interference accommodation is not required. Moreover, considering a flash ADC as an example of the low resolution (3-4 bit) IQ ADC, the PhADC has a lower theoretical energy limit than the flash ADC for a given phase ENOB. IQ offsets and amplitude mismatch impose unique nonlinearities on the PhADC due to the nonlinear amplitude-to-phase conversion. The understanding of this nonlinearity leads to a phase-domain mismatch and offset detection technique. Phase SNR is explicitly related to input noise for both ADCs, and to comparator offsets for the PhADC, respectively. All of the results prove that the PhADC is a promising quantization and demodulation solution.
Autors: Liu, Y.;Lotfi, R.;Hu, Y.;Serdijn, W.A.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 671 - 679
Publisher: IEEE
 
» A Comparison of Multiple Control Strategies for Vehicle Run-Off-Road and Return
Abstract:
A large percentage of single-vehicle automobile crashes involve a situation called run-off-road (ROR) where the vehicle leaves the roadway and travels on the surfaces adjacent to the road. Present solutions such as roadway infrastructure modifications and vehicle safety systems have helped to mitigate some ROR events but remain limited in their approach. A complete solution must also directly address the primary factor contributing to ROR crashes, which is driver performance errors. In this paper, four vehicle safety control systems, based on sliding (SL) control, linear quadratic (LQ), state flow, and classical theories, were developed to autonomously recover a vehicle from ROR without driver intervention. The vehicle response was simulated for each controller under a variety of common road departure and return scenarios. The results showed that the LQ and SL control methodologies outperformed the other controllers in terms of overall stability. However, the LQ controller was the only design to safely recover the vehicle in all of the simulation conditions examined. On average, it performed the recovery almost 50% faster and with 40% less lateral error than the SL controller at the expense of higher yaw rates.
Autors: Freeman, P.;Jensen, M.;Wagner, J.;Alexander, K.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Mar 2015, volume: 64, issue:3, pages: 901 - 911
Publisher: IEEE
 
» A comparison of thermoset and thermoplastic arc chutes in molded-case circuit breakers under fault clearing
Abstract:
Molded-case circuit breakers (MCCB) are vital devices that are used in many distribution systems for protection from faults in the network [1]. During a fault, a large increase in current passes through the terminals of the MCCB and the contacts open by electromagnetic actuation. On opening, a low-voltage arc is struck between the contacts, forming a high-temperature plasma of thousands of degrees Celsius [2]. The plasma causes thermal degradation of the insulating materials and erosion of the contacts and is a source of intense UV, which may further cause degradation of the insulating materials. In the case of a polyesterbased MCCB, electrically conductive soot is produced, which is detrimental to the long-term performance of the device.
Autors: R, B.T.;Chetwani, S.;Shrinet, V.;Oak, M.;Jain, S.;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Mar 2015, volume: 31, issue:2, pages: 30 - 35
Publisher: IEEE
 
» A Comprehensive Study on the Frequency-Dependent Electrical Characteristics of Sm2O3 MOS Capacitors
Abstract:
In this paper, we report comprehensive frequency-dependent electrical characterizations of samarium oxide (Sm2O3) MOS capacitors. The Sm2O3 crystal structure and phase identifications of the films were confirmed by X-ray diffractometry. The electrical characterizations were performed in the wide frequency ranges by the capacitance-voltage ( – ) and conductance-voltage ( – ) measurements at room temperature and series resistance effects were investigated following the correction of the measured – and G/ – characteristics. Significant changes have been observed in capacitance, especially in conductance curves following the corrections. Interestingly, the corrected conductance gives two distinct peaks in the corresponding depletion and inversion edge. The – characteristics in the low-frequency regions decrease with increasing in the frequency, in the high-frequency regions slightly increase with increasing in frequency. In addition, similar distinct behaviors have been observed for the calculated interface state density, diffusion, and barrier potential at low-high frequencies. The main reason of these behaviors can be - ttributed to the acceptor-/donor-like interface states and/or different relaxation time dependences of interface states. These results demonstrate that series resistance and interface states should be considered during the electrical characterization. Calculated interface density and barrier potential are suitable to use the Sm2O3 as a dielectric layer for MOS-based applications.
Autors: Kaya, S.;Yilmaz, E.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2015, volume: 62, issue:3, pages: 980 - 987
Publisher: IEEE
 
» A Contrario 2D Point Alignment Detection
Abstract:
In spite of many interesting attempts, the problem of automatically finding alignments in a 2D set of points seems to be still open. The difficulty of the problem is illustrated here by very simple examples. We then propose an elaborate solution. We show that a correct alignment detection depends on not less than four interlaced criteria, namely the amount of masking in texture, the relative bilateral local density of the alignment, its internal regularity, and finally a redundancy reduction step. Extending tools of the a contrario detection theory, we show that all of these detection criteria can be naturally embedded in a single probabilistic a contrario model with a single user parameter, the number of false alarms. Our contribution to the a contrario theory is the use of sophisticated conditional events on random point sets, for which expectation we nevertheless find easy bounds. By these bounds the mathematical consistency of our detection model receives a simple proof. Our final algorithm also includes a new formulation of the exclusion principle in Gestalt theory to avoid redundant detections. Aiming at reproducibility, a source code and an online demo open to any data point set are provided. The method is carefully compared to three state-of-the-art algorithms and an application to real data is discussed. Limitations of the final method are also illustrated and explained.
Autors: Lezama, J.;Morel, J.;Randall, G.;Gioi, R.G.v.;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Mar 2015, volume: 37, issue:3, pages: 499 - 512
Publisher: IEEE
 
» A Coordinated Voltage Control Approach for Coordination of OLTC, Voltage Regulator, and DG to Regulate Voltage in a Distribution Feeder
Abstract:
Integration of small-scale electricity generators, known as distributed generation (DG), into the distribution networks has become increasingly popular at the present. This tendency together with the falling price of the synchronous-type generator has potential to give DG a better chance at participating in the voltage regulation process together with other devices already available in the system. The voltage control issue turns out to be a very challenging problem for the distribution engineers since existing control coordination schemes would need to be reconsidered to take into account the DG operation. In this paper, we propose a control coordination technique, which is able to utilize the ability of DG as a voltage regulator and, at the same time, minimize interaction with other active devices, such as an on-load tap changing transformer and a voltage regulator. The technique has been developed based on the concept of control zone, line drop compensation, dead band, as well as the choice of controllers' parameters. Simulations carried out on an Australian system show that the technique is suitable and flexible for any system with multiple regulating devices including DG.
Autors: Muttaqi, K.M.;Le, A.D.T.;Negnevitsky, M.;Ledwich, G.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1239 - 1248
Publisher: IEEE
 
» A Decentralized Cloud Firewall Framework with Resources Provisioning Cost Optimization
Abstract:
Cloud computing is becoming popular as the next infrastructure of computing platform. Despite the promising model and hype surrounding, security has become the major concern that people hesitate to transfer their applications to clouds. Concretely, cloud platform is under numerous attacks. As a result, it is definitely expected to establish a firewall to protect cloud from these attacks. However, setting up a centralized firewall for a whole cloud data center is infeasible from both performance and financial aspects. In this paper, we propose a decentralized cloud firewall framework for individual cloud customers. We investigate how to dynamically allocate resources to optimize resources provisioning cost, while satisfying QoS requirement specified by individual customers simultaneously. Moreover, we establish novel queuing theory based model M/Geo/1 and M/Geo/m for quantitative system analysis, where the service times follow a geometric distribution. By employing Z-transform and embedded Markov chain techniques, we obtain a closed-form expression of mean packet response time. Through extensive simulations and experiments, we conclude that an M/Geo/1 model reflects the cloud firewall real system much better than a traditional M/M/1 model. Our numerical results also indicate that we are able to set up cloud firewall with affordable cost to cloud customers.
Autors: Liu, M.;Dou, W.;Yu, S.;Zhang, Z.;
Appeared in: IEEE Transactions on Parallel and Distributed Systems
Publication date: Mar 2015, volume: 26, issue:3, pages: 621 - 631
Publisher: IEEE
 
» A Decentralized Multiagent-Based Voltage Control for Catastrophic Disturbances in a Power System
Abstract:
In this paper, a multiagent-based voltage and reactive power control in the case of a multiple contingency is presented. Incorporating the agent-based autonomous feature to the intelligence of the remote terminal units, the present power system control structure can be used to help in preventing system voltage collapse during catastrophic disturbances. The control algorithm is based on a decentralized architecture of intelligent agents and the determination of a local zone that can carry out quick countermeasures in a decentralized manner as a multiagent system (MAS) during an emergency situation. An adaptive determination of the local zones undergoing voltage collapse has been developed based on the electrical distances among the generators and loads. Once assigned, the elements of the Jacobian matrix can be used to determine the optimum actions that need to be carried out at each power system element (such as increasing the voltages of generators and load shedding) within the assigned local zone. The contract net protocol is used for agent interactions. Simulation results using the IEEE-57 bus system show that the proposed method can act quickly to respond to emergency conditions to ensure that voltage collapse can be avoided.
Autors: Islam, S.R.;Muttaqi, K.M.;Sutanto, D.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1201 - 1214
Publisher: IEEE
 
» A Differential Algebraic Estimator for Sensorless Permanent-Magnet Synchronous Machine Drive
Abstract:
This paper describes a sensorless control for a high-performance permanent-magnet synchronous machine (PMSM) drive. A differential algebraic approach is used to estimate the position (and speed). The relationship thus obtained for analytical estimation of the position is based on the control voltages, the measured currents, and their derivatives. Unlike the other estimators like the extended Kalman filter (EKF) that is complex and computationally expensive, the differential algebraic estimator is simple with a 1-D model. Global convergence of the estimator is demonstrated, and experimental results show the effectiveness of the method and its robustness to current sensor fault.
Autors: Diao, S.;Diallo, D.;Makni, Z.;Marchand, C.;Bisson, J.;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Mar 2015, volume: 30, issue:1, pages: 82 - 89
Publisher: IEEE
 
» A Directional-Emission 1060-nm GaAs/InGaAs Microcylinder Laser
Abstract:
A GaAs/InGaAs microcylinder laser in diameter of m connected with a 2- m wide output waveguide is fabricated using standard photolithography and inductively coupled plasma etching technique. With the output waveguide, we realize the directional emission with the pulsed lasing operation wavelength of 1060 nm at room temperature. The maximum output power is W and the minimum threshold current is 2 mA, which is comparatively low compared with previous reported GaAs material microlasers. A single mode operation is achieved near threshold current at the wavelength of 1060 nm. Mode characteristics are calculated and analyzed by 2-D finite-difference time-domain simulation. The small volume, low threshold current, and low energy consumption make the GaAs/InGaAs microcylinder laser we presented a promising light source for optical interconnection on chip.
Autors: Li, M.;Zhou, X.;Ding, Y.;Chen, W.;Yu, H.;Kan, Q.;Li, S.;Mi, J.;Wang, W.;Pan, J.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Mar 2015, volume: 27, issue:6, pages: 569 - 572
Publisher: IEEE
 
» A Disassembly-Free Offline Detection and Condition Monitoring Technique for Eccentricity Faults in Salient-Pole Synchronous Machines
Abstract:
A novel scheme to reliably monitor the condition of static and dynamic eccentricity (DE) faults in salient-pole synchronous machines (SPSMs) through the standard short-circuit test is proposed in this paper. The detection technique is based on offline current signature analysis that does not require machine disassembly. The procedure is unaffected by machine saturation or supply voltage harmonics. In this scheme, DE fault is monitored by exploiting the presence of inherent static eccentricity (SE), whereas SE fault monitoring is achieved using residual estimation technique. The proposed method is found to work for both star and delta-connected machines. Results obtained from an experimental three-phase 2-kW SPSM have been used to validate the proposed eccentricity condition monitoring method.
Autors: Ilamparithi, T.;Nandi, S.;Subramanian, J.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1505 - 1515
Publisher: IEEE
 
» A Dynamic Attenuator Improves Spectral Imaging With Energy-Discriminating, Photon Counting Detectors
Abstract:
Energy-discriminating, photon counting (EDPC) detectors have high potential in spectral imaging applications but exhibit degraded performance when the incident count rate approaches or exceeds the characteristic count rate of the detector. In order to reduce the requirements on the detector, we explore the strategy of modulating the X-ray flux field using a recently proposed dynamic, piecewise-linear attenuator. A previous paper studied this modulation for photon counting detectors but did not explore the impact on spectral applications. In this work, we modeled detection with a bipolar triangular pulse shape (Taguchi , 2011) and estimated the Cramer-Rao lower bound (CRLB) of the variance of material selective and equivalent monoenergetic images, assuming deterministic errors at high flux could be corrected. We compared different materials for the dynamic attenuator and found that rare earth elements, such as erbium, outperformed previously proposed materials such as iron in spectral imaging. The redistribution of flux reduces the variance or dose, consistent with previous studies on benefits with conventional detectors. Numerical simulations based on DICOM datasets were used to assess the impact of the dynamic attenuator for detectors with several different characteristic count rates. The dynamic attenuator reduced the peak incident count rate by a factor of 4 in the thorax and 44 in the pelvis, and a 10 Mcps/mm EDPC detector with dynamic attenuator provided generally superior image quality to a 100 Mcps/mm detector with reference bowtie filter for the same dose. The improvement is more pronounced in the material images.
Autors: Hsieh, S.S.;Pelc, N.J.;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Mar 2015, volume: 34, issue:3, pages: 729 - 739
Publisher: IEEE
 
» A Fast Nondominated Sorting Guided Genetic Algorithm for Multi-Objective Power Distribution System Reconfiguration Problem
Abstract:
Distribution system reconfiguration (DSR) is a multi-objective, nonlinear problem. This paper introduces a new, fast, nondominated sorting genetic algorithm (FNSGA) for the purpose of solving the DSR problem in normal operation by satisfying all objectives simultaneously with a relatively small number of generations and relatively short computation time. The objectives of the problem are to minimize real power losses and improve the voltage profile and load balancing index with minimum switching operations. Instead of generating several ranks from the nondominated set of solutions, this algorithm deals with only one rank; then the most suitable solution is chosen according to the operator's wishes. If there is no preference and all objectives have the same degree of importance, the best solution is determined by simply considering the sum of the normalized objective values. Also, a guided mutation operation is applied instead of a random one to speed up convergence. Radial system topology is satisfied using graph theory by formulating the branch-bus incidence matrix (BBIM) and checking the rank of each topology. To test the algorithm, it was applied to two widely studied test systems and a real one. The results show the efficiency of this algorithm as compared to other methods in terms of achieving all the goals simultaneously with reasonable population and generation sizes and without using a mutation rate, which is usually problem-dependent.
Autors: Eldurssi, A.M.;O'Connell, R.M.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Mar 2015, volume: 30, issue:2, pages: 593 - 601
Publisher: IEEE
 
» A Framework for Secure Computations With Two Non-Colluding Servers and Multiple Clients, Applied to Recommendations
Abstract:
We provide a generic framework that, with the help of a preprocessing phase that is independent of the inputs of the users, allows an arbitrary number of users to securely outsource a computation to two non-colluding external servers. Our approach is shown to be provably secure in an adversarial model where one of the servers may arbitrarily deviate from the protocol specification, as well as employ an arbitrary number of dummy users. We use these techniques to implement a secure recommender system based on collaborative filtering that becomes more secure, and significantly more efficient than previously known implementations of such systems, when the preprocessing efforts are excluded. We suggest different alternatives for preprocessing, and discuss their merits and demerits.
Autors: Veugen, T.;de Haan, R.;Cramer, R.;Muller, F.;
Appeared in: IEEE Transactions on Information Forensics and Security
Publication date: Mar 2015, volume: 10, issue:3, pages: 445 - 457
Publisher: IEEE
 
» A Frequency Doubler/Modulator With 4.5 dBm Output Power at 170 GHz Using SiGe HBTs
Abstract:
A sub-terahertz frequency doubler with signal modulation is proposed and analyzed in this letter. An 85 GHz input signal is modulated by a differential pair, and a push-push frequency doubler with capacitive degeneration technique is designed to obtain the 170 GHz modulated output signal. Via the use of negative impedance to eliminate the leakage current of transistors, the proposed enhanced push-push frequency doubler achieves a power efficiency of 8.5% and a maximum output power of 4.5 dBm at 170 GHz without applying a modulation signal. The 0.13 SiGe BiCMOS process is used to fabricate the proposed design and the total chip area is 0.75 0.8 .
Autors: Li, Y.;Goh, W.L.;Xiong, Y.-Z.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Mar 2015, volume: 25, issue:3, pages: 181 - 183
Publisher: IEEE
 
» A Fully-Integrated Low-Dropout Regulator With Full-Spectrum Power Supply Rejection
Abstract:
A fully-integrated low-dropout regulator (LDO) with fast transient response and full spectrum power supply rejection (PSR) is proposed to provide a clean supply for noise-sensitive building blocks in wideband communication systems. With the proposed point-of-load LDO, chip-level high-frequency glitches are well attenuated, consequently the system performance is improved. A tri-loop LDO architecture is proposed and verified in a 65 nm CMOS process. In comparison to other fully-integrated designs, the output pole is set to be the dominant pole, and the internal poles are pushed to higher frequencies with only 50 of total quiescent current. For a 1.2 V input voltage and 1 V output voltage, the measured undershoot and overshoot is only 43 mV and 82 mV, respectively, for load transient of 0 to 10 mA within edge times of 200 ps. It achieves a transient response time of 1.15 ns and the figure-of-merit (FOM) of 5.74 ps. PSR is measured to be better than 12 dB over the whole spectrum (DC to 20 GHz tested). The prototype chip measures , including 140 pF of stacked on-chip capacitors.
Autors: Lu, Y.;Wang, Y.;Pan, Q.;Ki, W.-H.;Yue, C.P.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 707 - 716
Publisher: IEEE
 
» A Future Way of Storing Information: Resistive Random Access Memory.
Abstract:
Electronic information storage has become one of the major needs of modern societies, and it represents a market of more than US$5 billion [1]. Among all of the existing technologies, flash memory is the most widespread because of its simple structure, high integration, and fast speed [2]. The core cell of this device is based on the charge and discharge of a capacitor using a transistor as a tiny switch [3], but, as the devices are scaled down, this configuration presents some physical limitations [4]. Therefore, new ways for information storage are required, and, among all existing nonvolatile memories, one that has raised major expectations in recent years is resistive random access memory (RRAM) [5]. In this article, we present the working principle and functioning of the most promising RRAM devices for future information storage.
Autors: Ji, Y.;Hu, J.;Lanza, M.;
Appeared in: IEEE Nanotechnology Magazine
Publication date: Mar 2015, volume: 9, issue:1, pages: 12 - 17
Publisher: IEEE
 
» A G-Band Standing-Wave Push–Push VCO Using a Transmission-Line Resonator
Abstract:
In this paper, we propose a standing-wave push–push voltage-controlled oscillator (VCO) using a transmission-line (TL) resonator that covers a frequency range of 151–174 GHz. By properly distributing negative cells in the TL resonator, a wide frequency tuning range with low phase noise can be obtained. The electrical length of the TL resonator is determined to achieve a high second-harmonic output power. The fabricated VCO demonstrates a phase noise of 91.3 dBc/Hz at 1-MHz offset at a push–push output frequency of 151.1 GHz (the estimated result) and a tuning range of 14% with a dc power consumption of 33 mW at a 1-V supply voltage. The push–push output power ranges from 14.5 to 16 dBm. The figure-of-merit including the tuning range is 182.6 dBc/Hz.
Autors: Koo, H.;Kim, C.-Y.;Hong, S.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 1036 - 1045
Publisher: IEEE
 
» A Gecko-Inspired Electroadhesive Wall-Climbing Robot
Abstract:
Geckos can climb fast on vertical wall surfaces, whether dry or wet, smooth or rough. The principles of a gecko?s attachment abilities have been studied in detail, and wall-climbing robots based on the biomimetic adhesion of geckos have been proposed. However, the synthetic dry fibrillar adhesive that mimics the gecko?s adhesive footpad is still under development and does not yet achieve as high performances as a gecko. This adhesion method has some disadvantages, such as low payload and sensitivity to surface contaminants involving dust. Many studies have been conducted on the bionic design of robots to simulate a gecko?s motion but using other adhesive mechanisms instead. By combining the gecko?s motion modes and the specific adhesive mechanisms, various novel wall-climbing robots can be envisioned.
Autors: Chen, R.;
Appeared in: IEEE Potentials
Publication date: Mar 2015, volume: 34, issue:2, pages: 15 - 19
Publisher: IEEE
 
» A Generic Measurement Setup for Implementation and Performance Evaluation of Spectrum Sensing Techniques: Indoor Environments
Abstract:
Spectrum sensing is the preeminent task of both cognitive radios and next generation wireless networks. There are various spectrum sensing techniques and methods presented in the literature. Performance evaluation of these techniques and methods is an important issue from the perspective of both the receiver and system design. In this regard, experimental studies that involve implementation, measurement, and performance evaluation of these methods under realistic conditions are of paramount importance, along with the relevant theoretical work. Therefore, in this paper, a generic measurement methodology is proposed to implement various spectrum sensing techniques and evaluate their performances. Mobile and immobile scenarios; line-of-sight and non-line-of-sight conditions; and presence/absence of perfect spectral knowledge cases are all investigated for both energy detector (first-) and second-order statistical receivers. Results are presented along with relevant discussions. Future directions are outlined as well.
Autors: Yarkan, S.;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Mar 2015, volume: 64, issue:3, pages: 606 - 614
Publisher: IEEE
 
» A Generic Model of Memristors With Parasitic Components
Abstract:
In this paper, a generic model of memristive systems, which can emulate the behavior of real memristive devices is proposed. Non-ideal pinched hysteresis loops are sometimes observed in real memristive devices. For example, the hysteresis loops may deviate from the origin over a broad range of amplitude and frequency of the input signal. This deviation from the ideal case is often caused by parasitic circuit elements exhibited by real memristive devices. In this paper, we propose a generic memristive circuit model by adding four parasitic circuit elements, namely, a small capacitance, a small inductance, a small DC current source, and a small DC voltage source, to the memristive device. The adequacy of this model is verified experimentally and numerically with two thermistors (NTC and PTC) memristors.
Autors: Sah, M.P.;Yang, C.;Kim, H.;Muthuswamy, B.;Jevtic, J.;Chua, L.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 891 - 898
Publisher: IEEE
 
» A Globally Exponentially Stable Tracking Controller for Mechanical Systems Using Position Feedback
Abstract:
A solution to the problem of global exponential tracking of mechanical systems without velocity measurements is given in the technical note. The proposed controller is obtained combining a redesign of the recently reported exponentially stable immersion and invariance velocity observer and a new state-feedback passivity-based controller, which assigns to the closed-loop a port-Hamiltonian structure with a desired energy function. The result is applicable to a large class of mechanical systems including those with unbounded inertia matrix and possible presence of friction forces. Unlike previous results that rely on the presence—exact knowledge and pervasiveness—of these forces, our design treats them as disturbances, which are suitably compensated.
Autors: Romero, J.G.;Ortega, R.;Sarras, I.;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Mar 2015, volume: 60, issue:3, pages: 818 - 823
Publisher: IEEE
 
» A GPU-Accelerated Parallel Shooting Algorithm for Analysis of Radio Frequency and Microwave Integrated Circuits
Abstract:
This paper presents a new parallel shooting-Newton method based on a graphic processing unit (GPU)-accelerated periodic Arnoldi shooting solver (GAPAS) for fast periodic steady-state analysis of radio frequency/millimeter-wave integrated circuits. The new algorithm first explores a periodic structure of the state matrix by using a periodic Arnoldi algorithm for computing the resulting structured Krylov subspace in the generalized minimal residual (GMRES) solver. The resulting periodic Arnoldi shooting method is very amenable for massive parallel computing, such as GPUs. Second, the periodic Arnoldi-based GMRES solver in the shooting-Newton method is parallelized on the recent NVIDIA Tesla GPU platforms. We further explore CUDA GPUs features, such as coalesced memory access and overlapping transfers with computation to boost the efficiency of the resulting parallel GAPAS method. Experimental results from several industrial examples show that when compared with the state-of-the-art implicit GMRES method under the same accuracy, the new parallel shooting-Newton method can lead up to speedup.
Autors: Liu, X.;Yu, H.;Tan, S.X.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Mar 2015, volume: 23, issue:3, pages: 480 - 492
Publisher: IEEE
 
» A Heterogeneous Reconfigurable Cell Array for MIMO Signal Processing
Abstract:
This paper presents a heterogeneous reconfigurable cell array, designed for high-throughput baseband processing of multiple-input multiple-output (MIMO) systems. To achieve high performance and energy efficiency while retaining high flexibility, the proposed architecture adopts heterogeneous and hierarchical resource deployments. Additionally, extensive vector computation enhancements and flexible memory access schemes are employed to better support MIMO signal processing. Implemented in a 65 nm CMOS technology, the cell array occupies 8.88 core area and is capable of running at 500 MHz. For illustration, three computationally intensive blocks, namely channel estimation, channel matrix pre-processing, and hard-output data detection, of a 4 4 MIMO processing chain in a 20 MHz 64-QAM 3GPP long term evolution advanced (LTE-A) downlink are mapped and processed in real-time. Implementation results report a maximum throughput of 367.88 Mb/s with 1.49 nJ/b energy consumption. Compared to state-of-the-art designs, the proposed solution outperforms programmable platforms by several orders of magnitude in energy efficiency, and achieves similar level of efficiency to that of ASICs.
Autors: Zhang, C.;Liu, L.;Markovic, D.;Owall, V.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 733 - 742
Publisher: IEEE
 
» A Hierarchical Bayesian Degradation Model for Heterogeneous Data
Abstract:
Degradation data may be collected from a population with heterogeneous subpopulations. This paper contributes to the development of a new statistical modeling and computation method for analyzing heterogeneous degradation data. We adopt the random-coefficient degradation path approach, and propose a hierarchical Bayesian degradation model. To account for the heterogeneity, we model the unit-to-unit variability via random parameters in a Gaussian mixture model. We developed a computationally convenient algorithm that combines Gibbs sampling for parameter estimation as well as failure-time distribution prediction and Akaike information criterion for determining the number of subpopulations. A numerical example is used to illustrate the advantages of the proposed methodology over existing methods that do not explicitly consider heterogeneity in the degradation data.
Autors: Yuan, T.;Ji, Y.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2015, volume: 64, issue:1, pages: 63 - 70
Publisher: IEEE
 
» A Hierarchical Control Strategy With Fault Ride-Through Capability for Variable Frequency Transformer
Abstract:
A variable frequency transformer (VFT) is being considered as a new alternative to the classical back-to-back high voltage direct current (HVDC) link for interconnection of two asynchronous networks. The VFT is a retrospective form of frequency converter using the wound rotor induction machine (WRIM), which converts the constant frequency input into a variable frequency output. The prime objective of VFT is to achieve controlled bidirectional power transfer between the two asynchronous networks. This paper presents a detailed working principle of VFT technology and proposes a new hierarchical control strategy for establishing the VFT connection with two power systems to achieve bidirectional power transfer between them. Also, to restrict the grid fault propagation from one side of the VFT to the other side, a series dynamic braking resistor based fault ride-through (FRT) scheme is proposed. The performance of the VFT during the synchronization process, steady-state, dynamic, and the grid fault conditions is evaluated using the real-time hardware in-loop (HIL) system. The plant is simulated in real time using OPAL-RT real-time simulator while the control algorithm is implemented in digital signal processor to carry out HIL study. All the important results supporting the effectiveness of the proposed control strategy and FRT scheme are discussed.
Autors: Ambati, B.B.;Kanjiya, P.;Khadkikar, V.;El Moursi, M.S.;Kirtley, J.L.;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Mar 2015, volume: 30, issue:1, pages: 132 - 141
Publisher: IEEE
 
» A High-Power 105–120 GHz Broadband On-Chip Power-Combined Frequency Tripler
Abstract:
We report on the design, fabrication and characterization of a high-power and broadband 105–120 GHz Schottky diode frequency tripler based on a novel on-chip power combining concept that allows superior power handling than traditional approaches. The chip features twelve anodes on a 50 thick GaAs substrate. At room temperature, the tripler exhibits a 17% 3 dB bandwidth and a peak conversion efficiency for a nominal input power of around 350–400 mW, and efficiency for its maximum operational input power of 800–900 mW. This tripler can deliver maximum power levels very close to 200 mW. The on-chip power-combined frequency tripler is compared with a traditional tripler designed for the same band using the same design parameters.
Autors: Siles, J.V.;Lee, C.;Lin, R.;Chattopadhyay, G.;Reck, T.;Jung-Kubiak, C.;Mehdi, I.;Cooper, K.B.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Mar 2015, volume: 25, issue:3, pages: 157 - 159
Publisher: IEEE
 
» A High-Sensitivity Radar System Featuring Low Weight and Power Consumption
Abstract:
High-precision and sensitive radar is a challenging task and of great importance in today?s industrial, automotive, and medical applications. To promote this task at the student level, the Wireless Communications (MTT-20) and the Biological Effect and Medical Applications of RF and Microwave (MTT-10) Technical Committees coorganized an international High-Sensitivity Radar Student Design Competition for the first time. The contest was held during the 2014 IEEE Microwave Theory and Techniques Society International Microwave Symposium (IMS2014) in Tampa, Florida. The goal was to design a high-sensitivity monostatic radar system with minimum weight and power consumption that is able to detect the frequency of a moving target with sinusoidal motion. The target was placed at a 1-m distance, and the oscillation swing was limited to certain discrete values. Several radar system principles are applicable to achieve the desired design goals, each of them limited by specific constraints. The most popular ones are the frequency-modulated continuous wave (CW) [1], frequency-stepped CW [2], CW Doppler radar [3], and six-port radar [4]. Based on a careful evaluation of these system principles in the specific scenario, a CW radar architecture with a minimalistic hardware approach promised the best results. This article outlines the design considerations and presents the results of the hardware realization and signal processing algorithms of the winning radar system.
Autors: Mann, S.;Lurz, F.;Weigel, R.;Koelpin, A.;
Appeared in: IEEE Microwave Magazine
Publication date: Mar 2015, volume: 16, issue:2, pages: 99 - 105
Publisher: IEEE
 
» A High-Speed Protection Circuit for IGBTs Subjected to Hard-Switching Faults
Abstract:
This paper describes a high-speed protection circuit for insulated-gate bipolar transistors (IGBTs) subjected to hard-switching faults (HSFs). The reverse transfer capacitance depends on the collector–emitter voltage, and it produces a significant effect on the switching behavior not only under normal conditions but also under HSF conditions. A gate charge characteristic under HSF conditions differs from that under normal turn-on conditions. Hence, an HSF can be detected by monitoring both the gate–emitter voltage and the amount of gate charge during the turn-on transient period. IGBTs can be rapidly protected from destruction by using this method because a blanking time is unnecessary. Simulation and experiment verify the validity of the proposed high-speed protection circuit.
Autors: Horiguchi, T.;Kinouchi, S.;Nakayama, Y.;Oi, T.;Urushibata, H.;Okamoto, S.;Tominaga, S.;Akagi, H.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1774 - 1781
Publisher: IEEE
 
» A High-Speed Wafer-Scale CMOS X-Ray Detector With Column-Parallel ADCs Using Oversampling Binning Method
Abstract:
This paper presents a high-speed wafer-scale CMOS X-ray detector with an active area of cm, which features m-sized pixels. A horizontal row driver is adopted for implementing a three-side buttable detector with the tiling technique and thereby enabling the extension of the active area. The proposed detector employs 14-b column-parallel extended-counting analog-to-digital converters (EC ADCs) using digital correlated double sampling for high-speed operation and high-gray-scale resolution. The oversampling binning method using a modulator in EC ADCs is proposed for high sensitivity and the pipelined timing method is adopted for a high frame rate, which results in reduction of the X-ray dose. An offset cancellation method for the input buffer is used to improve the uniformity between column ADCs. The proposed CMOS X-ray detector is fabricated using a 0.35- m CMOS process with the stitching technique. The measured differential column fixed pattern noise and random noise without X-ray exposure are 3.01 and 3.06 least significant bits, respectively, at a resolution of 14 b. In the full-resolution mode, the proposed detector operates up to a frame frequency of 108 frames/s with the pipelined timing and 60 frames/s without the pipelined timing.
Autors: Kim, J.;Hong, S.;Kwon, O.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Mar 2015, volume: 62, issue:3, pages: 888 - 895
Publisher: IEEE
 
» A High-Throughput VLSI Architecture for Hard and Soft SC-FDMA MIMO Detectors
Abstract:
This paper introduces a novel low-complexity multiple-input multiple-output (MIMO) detector tailored for single-carrier frequency division-multiple access (SC-FDMA) systems, suitable for efficient hardware implementations. The proposed detector starts with an initial estimate of the transmitted signal based on a minimum mean square error (MMSE) detector. Subsequently, it recognizes less reliable symbols for which more candidates in the constellation are browsed to improve the initial estimate. An efficient high-throughput VLSI architecture is also introduced achieving a superior performance compared to the conventional MMSE detectors with less than 28% added complexity. The performance of the proposed design is close to the existing maximum likelihood post-detection processing (ML-PDP) scheme, while resulting in a significantly lower complexity, i.e., and times fewer Euclidean distance (ED) calculations in the 16-QAM and 64-QAM schemes, respectively. The proposed design for the 16-QAM scheme is fabricated in a 0.13 CMOS technology and fully tested, achieving a 1.332 Gbps throughput, reporting the first fabricated design for SC-FDMA MIMO detectors to-date. A soft version of the proposed architecture is also introduced, which is customized for coded systems.
Autors: Neshatpour, K.;Shabany, M.;Gulak, G.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 761 - 770
Publisher: IEEE
 
» A Hybrid Stochastic/Interval Approach to Transmission-Constrained Unit Commitment
Abstract:
This paper proposes a new transmission-constrained unit commitment method that combines the cost-efficient but computationally demanding stochastic optimization and the expensive but tractable interval optimization techniques to manage uncertainty on the expected net load. The proposed hybrid unit commitment approach applies the stochastic formulation to the initial operating hours of the optimization horizon, during which the wind forecasts are more accurate, and then switches to the interval formulation for the remaining hours. The switching time is optimized to balance the cost of unhedged uncertainty from the stochastic unit commitment against the cost of the security premium of the interval unit commitment formulation. These hybrid, stochastic, and interval formulations are compared using Monte Carlo simulations on a modified 24-bus IEEE Reliability Test System. The results demonstrate that the proposed unit commitment formulation results in the least expensive day-ahead schedule among all formulations and can be solved in the same amount of time as a full stochastic unit commitment. However, if the range of the switching time is reduced, the hybrid formulation in the parallel computing implementation outperforms the stochastic formulation in terms of computing time.
Autors: Dvorkin, Y.;Pandzic, H.;Ortega-Vazquez, M.A.;Kirschen, D.S.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Mar 2015, volume: 30, issue:2, pages: 621 - 631
Publisher: IEEE
 
» A Kalman Filtering Framework for Physiological Detection of Anxiety-Related Arousal in Children With Autism Spectrum Disorder
Abstract:
Objective: Anxiety is associated with physiological changes that can be noninvasively measured using inexpensive and wearable sensors. These changes provide an objective and language-free measure of arousal associated with anxiety, which can complement treatment programs for clinical populations who have difficulty with introspection, communication, and emotion recognition. This motivates the development of automatic methods for detection of anxiety-related arousal using physiology signals. While several supervised learning methods have been proposed for this purpose, these methods require regular collection and updating of training data and are, therefore, not suitable for clinical populations, where obtaining labelled data may be challenging due to impairments in communication and introspection. In this context, the objective of this paper is to develop an unsupervised and real-time arousal detection algorithm. Methods: We propose a learning framework based on the Kalman filtering theory for detection of physiological arousal based on cardiac activity. The performance of the system was evaluated on data obtained from a sample of children with autism spectrum disorder. Results: The results indicate that the system can detect anxiety-related arousal in these children with sensitivity and specificity of 99% and 92%, respectively. Conclusion and significance: Our results show that the proposed method can detect physiological arousal associated with anxiety with high accuracy, providing support for technical feasibility of augmenting anxiety treatments with automatic detection techniques. This approach can ultimately lead to more effective anxiety treatment for a larger and more diverse population.
Autors: Kushki, A.;Khan, A.;Brian, J.;Anagnostou, E.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Mar 2015, volume: 62, issue:3, pages: 990 - 1000
Publisher: IEEE
 
» A Kinesthetic Washout Filter for Force-Feedback Rendering
Abstract:
Today haptic feedback can be designed and associated to audiovisual content (haptic-audiovisuals or HAV). Although there are multiple means to create individual haptic effects, the issue of how to properly adapt such effects on force-feedback devices has not been addressed and is mostly a manual endeavor. We propose a new approach for the haptic rendering of HAV, based on a washout filter for force-feedback devices. A body model and an inverse kinematics algorithm simulate the user’s kinesthetic perception. Then, the haptic rendering is adapted in order to handle transitions between haptic effects and to optimize the amplitude of effects regarding the device capabilities. Results of a user study show that this new haptic rendering can successfully improve the HAV experience.
Autors: Danieau, F.;Lecuyer, A.;Guillotel, P.;Fleureau, J.;Mollet, N.;Christie, M.;
Appeared in: IEEE Transactions on Haptics
Publication date: Mar 2015, volume: 8, issue:1, pages: 114 - 118
Publisher: IEEE
 
» A Learning-to-Rank Approach to Software Defect Prediction
Abstract:
Pub DtlSoftware defect prediction can help to allocate testing resources efficiently through ranking software modules according to their defects. Existing software defect prediction models that are optimized to predict explicitly the number of defects in a software module might fail to give an accurate order because it is very difficult to predict the exact number of defects in a software module due to noisy data. This paper introduces a learning-to-rank approach to construct software defect prediction models by directly optimizing the ranking performance. In this paper, we build on our previous work, and further study whether the idea of directly optimizing the model performance measure can benefit software defect prediction model construction. The work includes two aspects: one is a novel application of the learning-to-rank approach to real-world data sets for software defect prediction, and the other is a comprehensive evaluation and comparison of the learning-to-rank method against other algorithms that have been used for predicting the order of software modules according to the predicted number of defects. Our empirical studies demonstrate the effectiveness of directly optimizing the model performance measure for the learning-to-rank approach to construct defect prediction models for the ranking task.
Autors: Yang, X.;Tang, K.;Yao, X.;
Appeared in: IEEE Transactions on Reliability
Publication date: Mar 2015, volume: 64, issue:1, pages: 234 - 246
Publisher: IEEE
 
» A Level-Set Method for Skinning Animated Particle Data
Abstract:
In this paper, we present a straightforward, easy to implement method for particle skinning-generating surfaces from animated particle data. We cast the problem in terms of constrained optimization and solve the optimization using a level-set approach. The optimization seeks to minimize the thin-plate energy of the surface, while staying between surfaces defined by the union of spheres centered at the particles. Our approach skins each frame independently while preserving the temporal coherence of the underlying particle animation. Thus, it is well-suited for environments where particle skinning is treated as a post-process, with each frame generated in parallel. Moreover, our approach is integrated with the OpenVDB library and the underlying partial differential equation is amenable to implicit time integration. We demonstrate our method on data generated by a variety of fluid simulation techniques and simple particle systems.
Autors: Bhattacharya, H.;Yue Gao;Bargteil, A.W.;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Mar 2015, volume: 21, issue:3, pages: 315 - 327
Publisher: IEEE
 
» A Lightweight Solution to perform Automatic Meter Reading using an Unmanned Aerial Vehicle
Abstract:
typically, electric power companies employ a group of employees known as power meter readers to collect data on the customer's energy consumption. This activity is carried out manually, which can lead to errors and cause financial and physical losses. There are several approaches with the aim at minimizing the aforementioned problems. These approaches propose different methodologies to discover routes that are more efficient for the power meter readers while performing their tasks. However, the problems associated with manual readings may occur even when the routes are more efficient. In addition, there are some proposals to achieve the automatic meter readings using cars. However, these proposals are limited to traffic congestions and present a high cost in terms of fuel. To overcome these challenges and limitations in the literature efforts, we propose an automatic meter reading system based on Unmanned Aerial Vehicles. The results show that our approach has two key contributions compared to other solutions in the literature: (i) power meter readers are no longer necessary; (ii) it reduces the time to perform the readings from the electric meters.
Autors: Rodrigues Torres Neto, Jose;Ludovico Guidoni, Daniel;Aparecido Villas, Leandro;
Appeared in: IEEE Latin America Transactions
Publication date: Mar 2015, volume: 13, issue:3, pages: 628 - 633
Publisher: IEEE
 
» A Linear Complexity Direct Volume Integral Equation Solver for Full-Wave 3-D Circuit Extraction in Inhomogeneous Materials
Abstract:
An -matrix based linear complexity direct matrix solution is developed for the volume integral equation (VIE) based broadband full-wave extraction of general 3-D circuits. Such circuits are in general electrically small or moderate, but contain arbitrarily shaped lossy conductors immersed in inhomogeneous dielectrics with ports located anywhere in the physical layout of the circuit. In the proposed direct solver, we first develop a well-conditioned VIE formulation without sacrificing the rigor and the advantages of the prevailing formulations. This formulation facilitates a robust direct solution of good accuracy even with a rank-1 representation. We then overcome the numerical challenge of solving the resultant highly unstructured system matrix mixed with both square and rectangular dense and sparse matrices by developing a fast linear complexity direct solution. This direct solution is capable of inverting dense matrices involving over 2 million unknowns in less than 1 h on a single CPU core running at 3 GHz. Numerical simulations of large-scale 3-D circuits and comparisons with state-of-the-art linear complexity iterative VIE solvers have demonstrated the accuracy, efficiency, and linear complexity of the proposed direct VIE solver.
Autors: Omar, S.;Jiao, D.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Mar 2015, volume: 63, issue:3, pages: 897 - 912
Publisher: IEEE
 
» A Low Component Count Series Voltage Compensation Scheme for DFIG WTs to Enhance Fault Ride-Through Capability
Abstract:
Fault ride-through (FRT) operation has been a challenge for the doubly fed induction generator (DFIG) based wind turbines (WTs) as the stator winding is directly connected to the grid. Additionally, several grid codes have been established for the grid interconnection of WTs, which demand the WT to stay connected and provide the predefined reactive current support to the grid during FRT operation. The series voltage compensation (SeVC) based FRT schemes for DFIG WTs outperforms all others in terms of smooth transient performance. However, such FRT schemes require an additional voltage-source converter (VSC) and a bulkier series transformer to provide the SeVC. This paper proposes a low component count SeVC scheme that is applicable to both individual WTs and wind parks to cope up with the recent grid codes requirements. The proposed configuration eliminates the need of a series transformer and an additional VSC for the SeVC operation with the use of three additional IGBTs/switches. Furthermore, a coordinated control strategy is proposed to control the WT that enhance its FRT capabilities. The proposed low component count FRT scheme and coordinated control strategy are validated using the detailed mathematical modeling and simulation of 1.5 MW DFIG WT.
Autors: Ambati, B.B.;Kanjiya, P.;Khadkikar, V.;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Mar 2015, volume: 30, issue:1, pages: 208 - 217
Publisher: IEEE
 
» A Low Phase Noise Injection-Locked Programmable Reference Clock Multiplier With a Two-Phase PVT-Calibrator for PLLs
Abstract:
A low phase noise injection-locked reference clock multiplier that can suppress the delta-sigma (ΔΣ) noise of ΔΣ phase-locked loops (PLLs) is proposed. By adopting a two-phase PVT-calibrator that switches the calibration resolution, the clock multiplier can reduce the frequency-acquisition time, as well as tightly regulate the real-time degradation of the phase noise. To improve the performance of the calibration method utilizing two identical oscillators, the self-injection pulse generator that balances the loadings of two oscillators is proposed. In addition, this work presents a systematic design methodology that minimizes the degradation of the phase noise over the PVT variations, based on the phase noise analysis of injection-locking. The clock multiplier was designed with the prototype ΔΣ PLL in the 65-nm CMOS process. It can provide five reference frequencies, i.e., 19.2, 28.8, 48, 57.6, and 96 MHz. The phase noise of the 96-MHz signal was -130.0 and -131.8 dBc/Hz at 100 kHz and 1 MHz offsets, respectively; the performance of low phase noise was confirmed over temperature variations. The total active area was 0.062 mm2, and the power consumption was 1.6-1.9 mW. By switching the reference frequency from 19.2 to 96 MHz, the phase noise of the prototype PLL at the 10-MHz offset from the 4.4-GHz signal was improved from -120.1 to -138.6 dBc/Hz.
Autors: Yongsun Lee;Mina Kim;Taeho Seong;Jaehyouk Choi;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Mar 2015, volume: 62, issue:3, pages: 635 - 644
Publisher: IEEE
 
» A Low-Cost Electric Field Energy Harvester for an MV/HV Asset-Monitoring Smart Sensor
Abstract:
This paper investigates the powering of smart grid sensors with electric fields (E-fields) present in abundance near most medium-voltage to high-voltage (MV/HV) utility assets. A unique E-field energy harvester is proposed, which is integrated into a sensor's enclosure, thereby ensuring low-cost and compact size. The proposed energy harvester can be used with multiple assets by virtue of its shape, which also allows installation without interruption of the MV/HV asset. Design methodology of the harvester through Maxwell simulations along with a new and efficient circuit design for obtaining a regulated dc supply is presented. A medium-voltage prototype of the proposed E-field energy harvester integrated with a wireless voltage sensor is built and tested on a 35-kV bus. The prototype provides 17 mW of continuous power at 35 kV with a high energy density. This power is enough to operate a low-duty-cycle sensor node stuck on to an MV/HV asset. The prototype shows promising results and demonstrates the efficacy of using E-fields for powering smart grid sensors for MV/HV assets.
Autors: Moghe, R.;Iyer, A.;Lambert, F.C.;Divan, D.;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Mar 2015, volume: 51, issue:2, pages: 1828 - 1836
Publisher: IEEE
 

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