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Electrical and Electronics Engineering publications abstract of: 02-2012 sorted by title, page: 0
» “Design for All in the Context of the Information Society”: Integration of a Specialist Course in a Generalist M.Sc. Program in Electrical and Electronics Engineering
Abstract:
This paper describes an educational research experience that took place in the Electrical & Electronics Engineering Master's program offered at the Escuela Universitaria de Ingeniería Técnica de Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain. The focus is to provide details of the motivation behind and the design and subsequent evaluation of a course adapted to the European Higher Education Area titled “ Design for All in the Context of the Information Society.” This course may be useful for other engineering educators who design Master's programs and perform research on education in electrical and electronics engineering. The course contents are structured along four axes: disabilities, technical aids, accessibility, and recommendations of the standardization bodies. The results of four years of experience are presented. The course is evaluated according to accepted criteria, highlighting the course scope, pedagogic decisions, and relevance. Based on the analysis of program outcomes, some recommendations are made for undergraduate and postgraduate engineering education programs focusing on disability and technology .
Autors: Godino-Llorente, J. I.;Fraile, R.;Gonzalez de Sande, J. C.;Osma-Ruiz, V.;Saenz-Lechon, N.;
Appeared in: IEEE Transactions on Education
Publication date: Feb 2012, volume: 55, issue:1, pages: 107 - 117
Publisher: IEEE
 
» 'Fingerprinting for food stamps' row triggers North American privacy debate
Abstract:
A row between New York Governor Andrew Cuomo who has called for New York City to stop requiring fingerprinting of its food stamp recipients, and the city's mayor, has fuelled the privacy debate in North American, where authorities are ramping up their use of biometrics to prevent fraud in areas ranging from access to food stamps, to law enforcement and border control.
Autors: [No author name available]
Appeared in: Biometric Technology Today
Publication date: Feb 2012
Publisher: Elsevier B.V.
 
» (Re)Designing Data-Centric Data Centers
Abstract:
A grand challenge facing computing today is to design future systems to efficiently manage and harvest useful insights from the growing amount of information. Emerging technology inflections provide a unique opportunity to address this challenge through novel redesign at both the hardware and software levels.
Autors: Ranganathan, Parthasarathy;Chang, Jichuan;
Appeared in: IEEE Micro
Publication date: Feb 2012, volume: 32, issue:1, pages: 66 - 70
Publisher: IEEE
 
» 0.6–3-GHz Wideband Receiver RF Front-End With a Feedforward Noise and Distortion Cancellation Resistive-Feedback LNA
Abstract:
A novel wideband receiver RF front-end, including a resistive negative feedback wideband low-noise amplifier (LNA) with feedforward noise and distortion cancellation and a current commutating down conversion passive mixer with biquad trans-impedance amplifier, is presented in this paper. In comparison to conventional resistive negative feedback LNAs, theory analysis and experimental results for the proposed LNA circuit shows improved performance parameters, including voltage gain, noise figure (NF), and input-referred third-order intercept point (IIP3), especially helpful for wideband LNA design in modern deep-submicrometer CMOS. A wideband receiver RF front-end fabricated in 0.13- CMOS, based on the proposed feedforward noise and distortion-cancellation resistive-feedback LNA, has 42–48-dB conversion gain with 0.8–12-MHz tunable IF 3-dB bandwidth and 12-dB adjacent channel selectivity at 2 , 14-dBm IIP3, and 3-dB NF double-sideband with 10-kHz flicker-noise corner frequency.
Autors: Wang, X.;Sturm, J.;Yan, N.;Tan, X.;Min, H.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 387 - 392
Publisher: IEEE
 
» 1 x 8 self-routing of 40 Gbit/s phase-modulated packets
Abstract:
A self-routing all-optical circuit for 40 Gbit/s DPSK optical packets is presented. The header information is self-processed to eventually drive an all-optical flip-flop, which serves as the optical pump in a coherent wavelength converter. Operation of the circuit is shown and switched optical packets with an overall limited penalty (~1 dB) are reported.
Autors: Presi, M.;Calabretta, N.;Porzi, C.;Corsini, R.;Contestabile, G.;Ciaramella, E.;
Appeared in: Electronics Letters
Publication date: Feb 2012, volume: 48, issue:3, pages: 169 - 171
Publisher: IEEE
 
» 1.4 MHz radio frequency metal-base transistor using single emitter layer
Abstract:
A report is presented on a study of single emitter layer metal base transistors with a base terminal made of aluminium grids. The latter exhibits low operating voltage associated to the high resistivity of the collector terminal and also shows very low leakage current. With such a single emitter layer, common-emitter current gain, on/off current ratio, and cutoff frequency of, respectively, 239.62, 3.8 x 107, and 1.4 MHz, were obtained.
Autors: Yusoff, A.R.B.M.;Sillva, W.J.D.;Song, Y.;Holz, E.;Schulz, D.;Shuib, S.A.;
Appeared in: Electronics Letters
Publication date: Feb 2012, volume: 48, issue:3, pages: 165 - 166
Publisher: IEEE
 
» 1.5-V-Operation Ultralow Power Circuit of Poly-Si TFTs Fabricated Using the NAOS Method
Abstract:
We have fabricated thin-film transistors (TFTs) and liquid-crystal displays (LCDs) with monolithic drivers on glass substrates and achieved ultralow power consumption by operating with a low power-supply voltage at 3 V. The gate insulator of the TFTs has a stack structure with an ultrathin interfacial layer formed by nitric acid oxidation of silicon and a 40-nm-thick layer formed by plasma-enhanced chemical vapor deposition. Owing to the TFTs with the thin gate insulator, the driving circuits of the LCDs can be operated at a supply voltage of 1.5 V, which is much lower than that of conventional LCDs of 10–15 V.
Autors: Kubota, Y.;Matsumoto, T.;Tsuji, H.;Suzuki, N.;Imai, S.;Kobayashi, H.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2012, volume: 59, issue:2, pages: 385 - 392
Publisher: IEEE
 
» 100-Gb/s optical transport network and beyond employing digital signal processing
Abstract:
We overview the requirements and the enabling technologies for optical transmission systems up to 100 Gb/s and beyond. Polarization- division multiplexed quadrature phase shift keying with digital coherent detection, and fast recovery in optical channel rerouting are key technologies for 100-Gb/s long-haul systems and beyond. We review test results of a realtime 80-channel wavelength-division multiplexing transmission over 420 km of field-installed fiber. Finally, we focus on digital nonlinear compensation and pilot tone phase noise compensation as technologies for systems beyond 100 Gb/s.
Autors: Yamazaki, E.;Tomizawa, M.;Miyamoto, Y.;
Appeared in: IEEE Communications Magazine
Publication date: Feb 2012, volume: 50, issue:2, pages: s43 - s49
Publisher: IEEE
 
» 1D/2D switchable grating based on field-induced polymer stabilized blue phase liquid crystal
Abstract:
We present a 1D/2D switchable grating based on field-induced polymer stabilized blue phase liquid crystal (PSBPLC). For 1D grating, the diffraction efficiency of the first order is 37.2% and the phase modulation depth of the 1D grating can achieve 2π. For 2D grating, more than 90% of light intensity is distributed to the surrounding orders of zero order and the phase modulation depth is about 3.67π. Furthermore it shows fast phase modulation and 1D/2D switching time.
Autors: Zhu, Ji-Liang;Lu, Jian-Gang;Qiang, Jing;Zhong, En-Wei;Ye, Zhi-Cheng;He, Zhenghong;Guo, Xiaojun;Dong, Cheng-Yuan;Su, Yikai;Shieh, Han-Ping D.;
Appeared in: Journal of Applied Physics
Publication date: Feb 2012, volume: 111, issue:3, pages: 033101 - 033101-5
Publisher: IEEE
 
» 2-ps Hard X-Ray Streak Camera Measurements at Sector 7 Beamline of the Advanced Photon Source
Abstract:
A hard X-ray streak camera capable of 2-ps time resolution is in operation at the Sector 7 beamline of the Advanced Photon Source. It is used for laser-pump, X-ray probe experiments using the Ti:Sapphire femtosecond laser system installed on the beamline. This streak camera, combined with standardized and prealigned experimental setups, can perform time-resolved liquid-phase absorption spectroscopy, reflectivity, and diffraction experiments.
Autors: Chollet, M.;Ahr, B.;Walko, D. A.;Rose-Petruck, C.;Adams, B.;
Appeared in: IEEE Journal of Selected Topics in Quantum Electronics
Publication date: Feb 2012, volume: 18, issue:1, pages: 66 - 73
Publisher: IEEE
 
» 2.7- Single-Frequency Low-Threshold Sb-Based Diode-Pumped External-Cavity VCSEL
Abstract:
We present the design, technology, and performances of a tunable Sb-based diode-pumped type-I quantum-well (QW) vertical-external-cavity surface-emitting lasers emitting at 2.7 . The half vertical-cavity surface-emitting laser (VCSEL) structure was grown by molecular beam epitaxy with quantum-well growth temperature of 440 . The sample was thermally annealed to optimize the QW gain design. We report on room-temperature continuous-wave laser with 0.17-mW output power and low threshold incident pump intensity of 0.7 kW/ while pumping at 830 nm with a commercial diode laser. The external cavity provides a circular beam with a low divergence of 3.6 . The short mm-long optical cavity laser exhibits tunable single frequency operation, with a sidemode suppression ratio , a linewidth , and a linear light polarization. Thermal and optical properties are studied.
Autors: Laurain, A.;Cerutti, L.;Myara, M.;Garnache, A.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2012, volume: 24, issue:4, pages: 246 - 248
Publisher: IEEE
 
» 20 Tbit/s Transmission Over 6860 km With Sub-Nyquist Channel Spacing
Abstract:
We demonstrate that channel spacing can be reduced to values smaller than the Nyquist channel spacing over transoceanic distance. Modulation memory induced by constrained transmitter bandwidth together with multisymbol detection can reduce intersymbol interference for systems with sub-Nyquist channel spacing. We transmit 198 100 G bandwidth constrained polarization-division-multiplexed return-to-zero quaternary phase shift keying channels with 400% spectral efficiency over 6860 km using 52 km spans of 150 m fiber and simple single-stage erbium-doped fiber amplifiers without any Raman amplification. We also show that 100 G coherent nonlinear performance scales differently with distance on uncompensated dispersion maps compared with direct detection transmission.
Autors: Cai, J.-X.;Davidson, C. R.;Lucero, A.;Zhang, H.;Foursa, D. G.;Sinkin, O. V.;Patterson, W. W.;Pilipetskii, A. N.;Mohs, G.;Bergano, N. S.;
Appeared in: Journal of Lightwave Technology
Publication date: Feb 2012, volume: 30, issue:4, pages: 651 - 657
Publisher: IEEE
 
» 2011 IEEE Conference on Computational Intelligence and Games [Conference Reports]
Abstract:
Autors: Kim, K.-J.;Cho, S.-B.;
Appeared in: IEEE Computational Intelligence Magazine
Publication date: Feb 2012, volume: 7, issue:1, pages: 15 - 18
Publisher: IEEE
 
» 2011 IEEE Congress on Evolutionary Computation [Conference Reports]
Abstract:
Autors: Smith, A.A.;
Appeared in: IEEE Computational Intelligence Magazine
Publication date: Feb 2012, volume: 7, issue:1, pages: 12 - 13
Publisher: IEEE
 
» 2011 International Joint Conference on Neural Networks (IJCNN 2011) [Conference Reports]
Abstract:
Autors: Minai, A.A.A.A.;
Appeared in: IEEE Computational Intelligence Magazine
Publication date: Feb 2012, volume: 7, issue:1, pages: 13 - 15
Publisher: IEEE
 
» 2012 BizTech Trends and Guidance
Abstract:
This list of the "2011 top 10 biztech trends" will provide guidance to business and technology executives to help them develop a high-level, long-term approach for exploiting opportunities to help the business grow.
Autors: Costello, Tom;
Appeared in: IT Professional
Publication date: Feb 2012, volume: 14, issue:1, pages: 64 - 63
Publisher: IEEE
 
» 3-D Finite Element Analysis of Additional Eddy Current Losses in Induction Motors
Abstract:
In this paper, an approach based on the three-dimensional finite element analysis is proposed to evaluate additional eddy current losses in induction motors of several MW. Losses produced by induced eddy currents in the end-region of the machine (stator clamping-plates and clamping-fingers) and losses provoked by parasitic leakage fields in the housing and in the metal parts of the cooling-ducts are investigated. Furthermore, excess rotor copper losses produced by higher harmonic fields in the rotor squirrel cage are taken into consideration as well. Comprehensive three-dimensional finite element models have been prepared in order to take these effects precisely into account. A numerical procedure based on nonconforming finite element meshes has been used in order to simplify the modeling procedure and the solving process has been carried out in the frequency domain with the aim of reducing the computational time.
Autors: Stermecki, A.;Biro, O.;Bakhsh, I.;Rainer, S.;Ofner, G.;Ingruber, R.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2012, volume: 48, issue:2, pages: 959 - 962
Publisher: IEEE
 
» 3-D Finite Element Modeling and Validation of Power Frequency Multishielding Effect
Abstract:
The electromagnetic (EM) barrier, the magnetic (M) shunt and a combination of both are widely used in electrical devices in order to control stray fields and effectively reduce the power loss that may lead to hazardous local overheating. This paper focuses on the 3-D finite element modeling and validation of multishielding at power frequencies. The hybrid (M+EM) shielding behavior of the current magnetic shunt configuration is numerically and experimentally examined and is compared to other types. The leakage flux complementary-based measurement method of stray-field loss is also proposed and verified based on the benchmark shielding models.
Autors: Cheng, Z.;Takahashi, N.;Forghani, B.;Liu, L.;Fan, Y.;Liu, T.;Zhang, J.;Wang, X.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2012, volume: 48, issue:2, pages: 243 - 246
Publisher: IEEE
 
» 3-D Integration of Robot Vision and Laser Data With Semiautomatic Calibration in Augmented Reality Stereoscopic Visual Interface
Abstract:
This paper proposes an augmented reality visualization interface to simultaneously present visual and laser sensors information further enhanced by stereoscopic viewing and 3-D graphics. The use of graphic elements is proposed to represent laser measurements that are aligned to video information in 3-D space. This methodology enables an operator to intuitively comprehend scene layout and proximity information and so to respond in an accurate and timely manner. The use of graphic elements to assist teleoperation, sometime discussed in the literature, is here proposed following an innovative approach that aligns virtual and real objects in 3-D space and color them suitably to facilitate comprehension of objects proximity during navigation. This paper is developed based on authors' previous experience on stereoscopic teleoperation. The approach is experimented on a real telerobotic system, where a user operates a mobile robot located several kilometers apart. The result showed simplicity and effectiveness of the proposed approach.
Autors: Livatino, S.;Banno, F.;Muscato, G.;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2012, volume: 8, issue:1, pages: 69 - 77
Publisher: IEEE
 
» 3-D Magnetic Scalar Potential Finite Element Formulation for Conducting Shells Coupled With an External Circuit
Abstract:
This paper presents a 3-D finite element formulation for a skin depth-independent shell element. With this formulation, thin conducting shells, which are multiply connected (i.e., having holes), and which can be coupled with an external circuit, can be modeled. This formulation takes into account the field variation through the depth due to skin effect. First, the method is described. Next, three numerical examples, including an automotive example, are presented.
Autors: Guerin, C.;Meunier, G.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2012, volume: 48, issue:2, pages: 323 - 326
Publisher: IEEE
 
» 3-D Model-Based Multiple-Object Video Tracking for Treatment Room Supervision
Abstract:
We present a method to monitor a patient and the equipment in a radiotherapy treatment room, by exploiting the information in the treatment plan, enriched with other elements such as visual, geometric, and “semantic” information. Using all these information items, and a generic model, a virtual environment of the scene is created, with maximum precision. The images resulting from video sequences with several cameras are also used to confront the filmed information on the scene and its numerical representation. The method is based on the features of the scene elements, and on a fuzzy formalism. The feasibility of the method is being quantitatively evaluated in the absence of treatment, to be further exploited in a module for external control by video in real conditions.
Autors: Portela Sotelo, M. A.;Desseree, E.;Moreau, J-.M.;Shariat, B.;Beuve, M.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Feb 2012, volume: 59, issue:2, pages: 562 - 570
Publisher: IEEE
 
» 3-D Posture and Gesture Recognition for Interactivity in Smart Spaces
Abstract:
Automatic perception of human posture and gesture from vision input has an important role in developing intelligent video systems. In this paper, we present a novel gesture recognition approach for human computer interactivity based on marker-less upper body pose tracking in 3-D with multiple cameras. To achieve the robustness and real-time performance required for practical applications, the idea is to break the exponentially large search problem of upper body pose into two steps: first, the 3-D movements of upper body extremities (i.e., head and hands) are tracked. Then using knowledge of upper body model constraints, these extremities movements are used to infer the whole 3-D upper body motion as an inverse kinematics problem. Since the head and hand regions are typically well defined and undergo less occlusion, tracking is more reliable and could enable more robust upper body pose determination. Moreover, by breaking the problem of upper body pose tracking into two steps, the complexity is reduced considerably. Using pose tracking output, the gesture recognition is then done based on longest common subsequence similarity measurement of upper body joint angles dynamics. In our experiment, we provide an extensive validation of the proposed upper body pose tracking from 3-D extremity movement which showed good results with various subjects in different environments. Regarding the gesture recognition based on joint angles dynamics, our experimental evaluation of five subjects doing six upper body gestures with average classification accuracies over 90% indicates the promise and feasibility of the proposed system.
Autors: Tran, C.;Trivedi, M. M.;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2012, volume: 8, issue:1, pages: 178 - 187
Publisher: IEEE
 
» 3D mechanical measurements with an atomic force microscope on 1D structures
Abstract:
We have developed a simple method to characterize the mechanical properties of three dimensional nanostructures, such as nanorods standing up from a substrate. With an atomic force microscope the cantilever probe is used to deflect a horizontally aligned nanorod at different positions along the nanorod, using the apex of the cantilever itself rather than the tip normally used for probing surfaces. This enables accurate determination of nanostructures’ spring constant. From these measurements, Young's modulus is found on many individual nanorods with different geometrical and material structures in a short time. Based on this method Young's modulus of carbon nanofibers and epitaxial grown III-V nanowires has been determined.
Autors: Kallesøe, Christian;Larsen, Martin B.;Bøggild, Peter;Mølhave, Kristian;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 023704 - 023704-7
Publisher: IEEE
 
» 3D Thermal-Aware Floorplanner using a MILP Approximation
Abstract:
One of the most important concerns in 3D technology is heat removal. In this paper we propose a 3D thermal-aware floorplanner. Our contributions include: (1) a novel multi-objective formulation to consider the thermal and performance constraints in the optimization approach; (2) an efficient Mixed Integer Linear Programming (MILP) representation of the floorplanning model; and (3) a smooth integration of the MILP model with an accurate thermal modelling of the architecture. The experimental results for several realistic 3D stacks based on the Niagara system show promising improvements of the main thermal metrics, with a reduced overhead in the wire length of the system.
Autors: David Cuesta, José L. Risco-Martin, José L. Ayala
Appeared in: Microprocessors and Microsystems
Publication date: Feb 2012
Publisher: Elsevier B.V.
 
» 40-Gb/s NRZ-to-RZ and OOK-to-BPSK Format and Wavelength Conversion on a Single SOA-MZI for Gridless Networking Operations
Abstract:
We propose and experimentally demonstrate simultaneous format and wavelength conversion at 40 Gb/s exploiting a single commercial semiconductor optical amplifier Mach–Zehnder interferometer. Conversion from nonreturn-to-zero (NRZ) to a 2-ps return-to-zero (RZ) on-off keying (OOK) format suitable for grooming onto a 160-Gb/s optical time-division-multiplexing frame is achieved. Furthermore, for the first time to the best of our knowledge, 40-Gb/s conversion from RZ OOK to RZ binary phase-shift keying (BPSK) is achieved. The effectiveness of the proposed scheme is demonstrated by means of bit-error-rate measurements. Error-free operations are reported, with a power penalty of 0.5 dB for the case of NRZ-to-RZ OOK conversion and of 3 dB (comprehensive of the degradation due to the wavelength conversion used to generate the probe signal) for the case of OOK-to-BPSK conversion.
Autors: Fresi, F.;Scaffardi, M.;Amaya, N.;Nejabati, R.;Simeonidou, D.;Bogoni, A.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2012, volume: 24, issue:4, pages: 279 - 281
Publisher: IEEE
 
» 45.8 and 125 Gb/s CP-QPSK/CP-BPSK Field Trial Over Installed Submarine Cable
Abstract:
We show successful transmission of 45.8 and 125 Gb/s coherent-detected polarization-multiplexed quadrature phase-shift keying (CP-QPSK) over both 2054 and 4108 km of 10 Gb/s nonreturn-to-zero-optimized field-deployed submarine cable. Moreover, we report successful transmission of 45.8 Gb/s coherent-detected polarization-multiplexed binary phase-shift keying (CP-BPSK) over 9420 km of legacy submarine fiber. We present single-channel transmission results, as well as wavelength-division multiplexed (WDM) transmission results with copropagating WDM channels placed on a 100 GHz and on a 50 GHz grid, where we optimized the transmission performance by sweeping the launch power and precompensation. For 45.8 Gb/s CP-QPSK, a margin with respect to the forward error correction (FEC) limit of 1.7 dBQ was obtained after transmitting over a 4108 km distance in a 50 GHz grid WDM configuration. Considering the transmission of 125 Gb/s CP-QPSK over the same distance and with the same channel configuration, a 1.1 dBQ margin was measured, showing the feasibility of a tenfold increase in transmission capacity over legacy submarine fiber. This significantly delays the costly alternative of deploying a new submarine cable. For the transmission of a 45.8 Gb/s CP-BPSK modulated signal on a 50 GHz WDM grid over a 9420 km distance, a margin of 1.2 dBQ with respect to the FEC limit is reported. This underlines the great robustness of CP-BPSK toward nonlinear fiber impairments and thereby the feasibility to cross transoceanic distances with this modulation format.
Autors: Sleiffer, V. A. J. M.;Veljanovski, V.;van den Borne, D.;Capasso, J.;Kuluslu, H.;Seixas, J.;Schramm, V.;Tschersich, A.;Nogueira, R.;Pavlovic, N. B.;Ivarson, K.;Spaelter, S.;de Waardt, H.;
Appeared in: Journal of Lightwave Technology
Publication date: Feb 2012, volume: 30, issue:4, pages: 624 - 633
Publisher: IEEE
 
» 50-Gb/s Silicon Optical Modulator
Abstract:
Optical modulators formed in silicon are the keystone to many low cost optical applications. Increasing the data rate of the modulator benefits the efficiency of channel usage and decreases power consumption per bit of data. Silicon-based modulators which operate via carrier depletion have to the present been demonstrated at data rates up to 40 Gb/s; however, here we present for the first time optical modulation at 50 Gb/s with a 3.1-dB extinction ratio obtained from carrier depletion based phase shifter incorporated in a Mach–Zehnder interferometer. A corresponding optical insertion loss of approximately 7.4 dB is measured.
Autors: Thomson, D. J.;Gardes, F. Y.;Fedeli, J.-M.;Zlatanovic, S.;Hu, Y.;Kuo, B. P. P.;Myslivets, E.;Alic, N.;Radic, S.;Mashanovich, G. Z.;Reed, G. T.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2012, volume: 24, issue:4, pages: 234 - 236
Publisher: IEEE
 
» 68.4 μW 400 MHz intrabody communication receiver front-end for biomedical applications
Abstract:
A 400 MHz sub-hundred microwatt intrabody communication receiver front-end suitable for OOK, ASK and FSK modulation schemes and applied to personal health wearable/implantable devices is presented. 68.4 μW of static power, 24.1 dB of gain, at least 18 dB fundamental above distortions and 167 x 118 μm2 of core size are achieved in 0.18 μm CMOS technology.
Autors: Shih, H.-Y.;Chang, Y.-C.;
Appeared in: Electronics Letters
Publication date: Feb 2012, volume: 48, issue:3, pages: 143 - 144
Publisher: IEEE
 
» 7-Tb/s Signal Transmission Over 320 km Using PDM-64QAM Modulation
Abstract:
We have transmitted a signal over 320-km conventional single mode fiber (SMF-28) with hybrid amplifier spans of 80 km. Each terabit superchannel comprises ten Nyquist wavelength division multiplexing polarization division multiplexing 64 quadrature amplitude modulation subchannels occupying 137.5 GHz, which gives a spectral-efficiency of 7.65 b/s/Hz per superchannel. The bit error ratio of all channels after transmission over 320 km is measured smaller than , the soft-decision forward error correction limit.
Autors: Yu, J.;Dong, Z.;Chien, H.-C.;Shao, Y.;Chi, N.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2012, volume: 24, issue:4, pages: 264 - 266
Publisher: IEEE
 
» -Regularized STAP Algorithms With a Generalized Sidelobe Canceler Architecture for Airborne Radar
Abstract:
In this paper, we propose novel -regularized space-time adaptive processing (STAP) algorithms with a generalized sidelobe canceler architecture for airborne radar applications. The proposed methods suppose that a number of samples at the output of the blocking process are not needed for sidelobe canceling, which leads to the sparsity of the STAP filter weight vector. The core idea is to impose a sparse regularization ( -norm type) to the minimum variance criterion. By solving this optimization problem, an -regularized recursive least squares ( -based RLS) adaptive algorithm is developed. We also discuss the SINR steady-state performance and the penalty parameter setting of the proposed algorithm. To adaptively set the penalty parameter, two switched schemes are proposed for -based RLS algorithms. The computational complexity analysis shows that the proposed algorithms have the same complexity level as the conventional RLS algorithm , where is the filter weight vector length), but a significantly lower complexity level than the loaded sample covariance matrix inversion algorithm and the compressive sensing STAP algorithm ( , where is the angle-Doppler plane size). The simulation results show that the proposed STAP algorithms converge- - rapidly and provide a SINR improvement using a small number of snapshots.
Autors: Yang, Z.;de Lamare, R. C.;Li, X.;
Appeared in: IEEE Transactions on Signal Processing
Publication date: Feb 2012, volume: 60, issue:2, pages: 674 - 686
Publisher: IEEE
 
» : A New Physics-Based Explicit Compact Model for Lightly Doped Short-Channel Triple-Gate SOI MOSFETs
Abstract:
In this paper, we present a new compact drain-current model for double-gate or triple-gate silicon on insulator (SOI) metal–oxide–semiconductor field-effect transistors, which is based on a physics-based 3-D analysis. Explicit analytical model equations for the height of the potential barrier are derived in closed form from a 3-D model for the channel electrostatics without the need to introduce any fitting parameter. The device current is described by a superposition of a surface-channel current above threshold and a center current in the subthreshold region, accounting for the movement of the most leaky path in the device cross section. Comparison with Technology Computer Aided Design (TCAD) shows a good scalability of the model down to a gate length of 30 nm. Furthermore, the characteristics are compared with measurements and obtain accurate results down to an effective channel length of 53 nm.
Autors: Kloes, A.;Schwarz, M.;Holtij, T.;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2012, volume: 59, issue:2, pages: 349 - 358
Publisher: IEEE
 
» -Divergence Estimation and Two-Sample Homogeneity Test Under Semiparametric Density-Ratio Models
Abstract:
A density ratio is defined by the ratio of two probability densities. We study the inference problem of density ratios and apply a semiparametric density-ratio estimator to the two-sample homogeneity test. In the proposed test procedure, the -divergence between two probability densities is estimated using a density-ratio estimator. The -divergence estimator is then exploited for the two-sample homogeneity test. We derive an optimal estimator of -divergence in the sense of the asymptotic variance in a semiparametric setting, and provide a statistic for two-sample homogeneity test based on the optimal estimator. We prove that the proposed test dominates the existing empirical likelihood score test. Through numerical studies, we illustrate the adequacy of the asymptotic theory for finite-sample inference.
Autors: Kanamori, T.;Suzuki, T.;Sugiyama, M.;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2012, volume: 58, issue:2, pages: 708 - 720
Publisher: IEEE
 
» -Divergence Estimation and Two-Sample Homogeneity Test Under Semiparametric Density-Ratio Models
Abstract:
A density ratio is defined by the ratio of two probability densities. We study the inference problem of density ratios and apply a semiparametric density-ratio estimator to the two-sample homogeneity test. In the proposed test procedure, the -divergence between two probability densities is estimated using a density-ratio estimator. The -divergence estimator is then exploited for the two-sample homogeneity test. We derive an optimal estimator of -divergence in the sense of the asymptotic variance in a semiparametric setting, and provide a statistic for two-sample homogeneity test based on the optimal estimator. We prove that the proposed test dominates the existing empirical likelihood score test. Through numerical studies, we illustrate the adequacy of the asymptotic theory for finite-sample inference.
Autors: Kanamori, T.;Suzuki, T.;Sugiyama, M.;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2012, volume: 58, issue:2, pages: 708 - 720
Publisher: IEEE
 
» and Codoped Tellurite Optical Fiber for Lasers and Amplifiers in the Near-Infrared Wavelength Region: Fabrication, Optical Characterization, and Prospects
Abstract:
A tellurite optical fiber doped with and ions was designed and fabricated with the aim of assessing its suitability as laser and optical amplifier operating at 1550 nm, compatible with silica fiber standard dimensions. High-quality optical fibers, with an attenuation loss of 1.0 dB/m at 1320 nm, were obtained featuring a 6- diameter core. A fiber laser emitting at 1550 nm upon pumping at 976 nm and a fiber amplifier characterized by signal amplification of 8 dB for a length of 10 cm were demonstrated.
Autors: Lousteau, J.;Boetti, N.;Chiasera, A.;Ferrari, M.;Abrate, S.;Scarciglia, G.;Venturello, A.;Milanese, D.;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2012, volume: 4, issue:1, pages: 194 - 204
Publisher: IEEE
 
» -Regularized STAP Algorithms With a Generalized Sidelobe Canceler Architecture for Airborne Radar
Abstract:
In this paper, we propose novel l1-regularized space-time adaptive processing (STAP) algorithms with a generalized sidelobe canceler architecture for airborne radar applications. The proposed methods suppose that a number of samples at the output of the blocking process are not needed for sidelobe canceling, which leads to the sparsity of the STAP filter weight vector. The core idea is to impose a sparse regularization (l1-norm type) to the minimum variance criterion. By solving this optimization problem, an l1-regularized recursive least squares (l1-based RLS) adaptive algorithm is developed. We also discuss the SINR steady-state performance and the penalty parameter setting of the proposed algorithm. To adaptively set the penalty parameter, two switched schemes are proposed for l1-based RLS algorithms. The computational complexity analysis shows that the proposed algorithms have the same complexity level as the conventional RLS algorithm (O((NM)2)), where NM is the filter weight vector length), but a significantly lower complexity level than the loaded sample covariance matrix inversion algorithm (O((NM)3)) and the compressive sensing STAP algorithm (O((NsNd)3), where N8Nd >; NM is the angle-Doppler plane size). The simulation results show that the proposed STAP algorithms converge rapidly and provide a SINR improvement using a small number of snapshots.
Autors: Zhaocheng Yang;de Lamare, R.C.;Xiang Li;
Appeared in: IEEE Transactions on Signal Processing
Publication date: Feb 2012, volume: 60, issue:2, pages: 674 - 686
Publisher: IEEE
 
» A 0.01–8-GHz (12.5 Gb/s) 4 4 CMOS Switch Matrix
Abstract:
This paper presents a 0.01–8-GHz 4 4 switch matrix in 0.13- CMOS technology. A deep n-well series–shunt–series switch is chosen as the switching core, and the transistor sizes are optimized for low insertion loss and high isolation up to 8 GHz. Full electromagnetic analysis is also performed on the switching core to result in a compact design. The 4 4 switch matrix shows a measured insertion loss of 2.0–3.3 dB and an isolation of 50–44 dB at 2–8 GHz with near-zero power consumption. The measured input and are 8–10 and 26–30 dBm at 0.5–8 GHz. The switch matrix has very low dispersion with group-delay variation and can switch a 12.5-Gb/s signal with a bit error rate of . The design can be used in reconfigurable 0.01–8 GHz communication systems or as a crossbar switch matrix for data routing.
Autors: Shin, D.;Kang, D.-W.;Rebeiz, G. M.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 381 - 386
Publisher: IEEE
 
» A 0.018% THD+N, 88-dB PSRR PWM Class-D Amplifier for Direct Battery Hookup
Abstract:
A low-distortion third-order class-D amplifier that is fully integrated into a 0.18- m CMOS process was designed for direct battery hookup in a mobile application. A class-D amplifier for direct battery hookup must have a sufficiently high power supply rejection ratio (PSRR) in preparation for noise, such as when a global system for mobile communications (GSM) bursts ripples through the system power line. This amplifier has a high PSRR of 88 dB for 217-Hz power supply ripples, using a third-order loop filter. System performance and stability are improved by applying the design technique of input-feedforward delta-sigma modulators to the pulse-width modulation (PWM) class-D amplifier. A filterless method that can remove the external LC filter is employed, which offers great advantages in terms of PCB space and system cost. This amplifier achieves a power efficiency of 85.5% while delivering an output power of 750 mW into an 8- load from a 3.7-V supply voltage. Maximum achieved output power at 1% total harmonic distortion plus noise (THD+N) from a 4.9-V supply voltage into an 8- load is 1.15 W. This class-D amplifier is designed to have a broad operational range of 2.7–4.9 V for the direct use of mobile phone battery power. It has a total area of 1.01 mm and achieves a THD+N of 0.018%.
Autors: Choi, Y.;Tak, W.;Yoon, Y.;Roh, J.;Kwon, S.;Koh, J.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 454 - 463
Publisher: IEEE
 
» A 0.18 CMOS Self-Mixing Frequency Tripler
Abstract:
A self-mixing frequency tripler with fundamental frequency between 6–7.3 GHz is built by cascading a doubler and a single-balanced mixer. The doubler and the mixer share a transconducting inductor to reduce the tripler core size when fabricated using the TSMC 0.18 RF mixed signal 1P6M process. When the input signal frequency is 6.5 GHz at the power level of 3 dBm, the measured conversion gain is 9.5 dB, the HRR1 is 21.5 dBc, the HRR2 is 29 dBc, and the total dc power consumption is 18.8 mW.
Autors: Lo, Y.-T.;Kiang, J.-F.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2012, volume: 22, issue:2, pages: 79 - 81
Publisher: IEEE
 
» A 0.6-V 30 GHz CMOS Quadrature VCO Using Microwave 1:1:1 Trifilar Transformer
Abstract:
A 30 GHz trifilar-transformer-coupled quadrature voltage-controlled oscillator (QVCO) is proposed in this letter using 0.13 CMOS technology. The trifilar transformer provides dc decoupling as well as ac mutual coupling from drain, gate, and source nodes. The mutual coupling increases the overall quality factor while the gate/drain-to-source coupling provides quadrature coupling. The proposed 1:1:1 trifilar transformer realization has lower ohmic loss than the conventional trifilar transformer realization and is especially suitable for high-frequency applications. As a result, the proposed 30 GHz QVCO has a figure of merit (FOM) and a maximum 41.6 dB sideband rejection (SBR) at a 0.6 V supply.
Autors: Syu, J.-S.;Lu, H.-L.;Meng, C.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2012, volume: 22, issue:2, pages: 88 - 90
Publisher: IEEE
 
» A 1.2 V, 0.87–3.7 GHz Wideband Low-Noise Mixer Using a Current Mirror for Multiband Application
Abstract:
A low-noise, ultra-wideband (UWB) mixer using a current mirror is proposed for multiband applications. The proposed mixer combines the advantages of both a passive mixer and an active mixer such as a low noise figure, low supply voltage operation, and high gain as well as wideband operation by switching the mirroring node of the current mirror. Moreover, the characteristic of wideband operation of the current mirror allows UWB operation. The proposed mixer operates from 870 MHz to 3.7 GHz. The fully integrated UWB mixer is fabricated in 0.13 CMOS technology with IIP3 of , gain of 13.5 ~ 14 dB, and noise figure of 2.9 ~ 6.5 dB. It consumes 16.8 mW of power with a supply voltage of 1.2 V in the band from 870 MHz to 3.7 GHz.
Autors: Na, D.;Kim, T. W.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2012, volume: 22, issue:2, pages: 91 - 93
Publisher: IEEE
 
» A 1.2 V, 130 nm CMOS parallel continuous-timeADC for OFDM UWB receivers
Abstract:
The design and implementation in a 1.2 V, 130 nm CMOS technology of a parallel continuous-timemodulator for OFDM UWB signals is described. Once the parallel architecture and the metrics used are presented, the NTF is optimized and implemented using a third order lowpass and a fourth order bandpass modulator. Both are CRFB structures which use active-RCintegrators. Then, the circuital blocks are discussed and some comments about the test set-up are given. Experimental results show good agreement with both system-level and layout-level simulations, with up to 15 dB DR for QPSK modulation over a signal bandwidth of 528 MHz, with a 62.3 mW power consumption.
Autors: Jokin Segundo, Jesús Arias, Luis Quintanilla, Lourdes Enríquez, Jesús M. Hernández, ...
Appeared in: Microelectronics Journal
Publication date: Feb 2012
Publisher: Elsevier B.V.
 
» A 130 nm 1.2 V/3.3 V 16 Kb Spin-Transfer Torque Random Access Memory With Nondestructive Self-Reference Sensing Scheme
Abstract:
Among all the emerging memories, Spin-Transfer Torque Random Access Memory (STT-RAM) has demonstrated many promising features such as fast access speed, nonvolatility, excellent scalability, and compatibility to CMOS process. However, the large process variations of both magnetic tunneling junction (MTJ) and MOS transistors in the scaled technologies severely limit the yield of STT-RAM chips. In this work, we proposed a new sensing scheme, named as nondestructive self-reference sensing, or NSRS, for STT-RAM. By leveraging the different dependencies of the high and low resistance states of MTJs on the cell current amplitude, the proposed NSRS technique can work well at the scenario when bit-to-bit variation of MTJ resistances is large. Furthermore, we proposed three combined magnetic- and circuit-level techniques, including R-I curve skewing, yield-driven cell current selection, and ratio matching, to further improve the sense margin and robustness of NSRS sensing scheme. The measurement results of a 16 Kb STT-RAM test chip show that our proposed nondestructive self-reference sensing technique can reliably readout all the measured memory bits, of which 10% read failure rate was observed by using the conventional sensing technique. The three enhancement technologies ensure a 20 mV minimum sense margin and the whole sensing process can complete within 15 ns.
Autors: Chen, Y.;Li, H.;Wang, X.;Zhu, W.;Xu, W.;Zhang, T.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 560 - 573
Publisher: IEEE
 
» A 175 GHz HBV Frequency Quintupler With 60 mW Output Power
Abstract:
In this letter, we present a fixed tuned 175 GHz frequency quintupler with 60 mW output power. The peak efficiency is 6.3% and the 3 dB bandwidth is 8 GHz. The multiplier is based on a single Heterostructure Barrier Varactor (HBV) diode that is flip-chip soldered into a microtsrip matching circuit. All the matching is done “on-chip” and there is no need for dc bias. The multiplier block is very compact .
Autors: Bryllert, T.;Malko, A.;Vukusic, J.;Stake, J.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2012, volume: 22, issue:2, pages: 76 - 78
Publisher: IEEE
 
» A 2 Degree-of-Freedom SOI-MEMS Translation Stage With Closed-Loop Positioning
Abstract:
This paper presents the design, analysis, fabrication, and characterization of a closed-loop XY micropositioning stage. The stage design is based on a 2 degree-of-freedom parallel kinematic mechanism with linear characteristics. Integrated with sensing combs, and fabricated in SOI wafers, the design provides a promising pathway to closed-loop positioning microelectromechanical systems platform with applications in nanomanufacturing and metrology. The XY stage provides a motion range of 20 micrometers in each direction at the driving voltage of 100 V. The resonant frequency of the XY stage under ambient conditions is 600 Hz. The positioning loop is closed using a capacitance-to-voltage conversion IC and a feedback controller is used to control position with an uncertainty characterized by a standard distribution of 5.24 nm and a closed-loop bandwidth of about 30 Hz. [2011-0149]
Autors: Koo, B.;Zhang, X.;Dong, J.;Salapaka, S. M.;Ferreira, P. M.;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Feb 2012, volume: 21, issue:1, pages: 13 - 22
Publisher: IEEE
 
» A 2.45 GHz electron cyclotron resonance proton ion source and a dual-lens low energy beam transport
Abstract:
The structure and preliminary commissioning results of a new 2.45 GHz ECR proton ion source and a dual-lens low energy beam transport (LEBT) system are presented in this paper. The main magnetic field of the ion source is provided by a set of permanent magnets with two small electro-solenoid magnets at the injection and the extraction to fine tune the magnetic field for better microwave coupling. A 50 keV pulsed proton beam extracted by a three-electrode mechanism passes through the LEBT system of length of 1183 mm. This LEBT consists of a diagnosis chamber, two Glaser lenses, two steering magnets, and a final beam defining cone. A set of inner permanent magnetic rings is embedded in each of the two Glaser lenses to produce a flatter axial-field to reduce the lens aberrations.
Autors: Zhang, W. H.;Ma, H. Y.;Yang, Y.;Wu, Q.;Zhang, X. Z.;Wang, H.;Ma, B. H.;Feng, Y. C.;Fang, X.;Guo, J. W.;Cao, Y.;Li, X. X.;Zhu, Y. H.;Li, J. Y.;Sha, S.;Lu, W.;Lin, S. H.;Guo, X. H.;Zhao, H. Y.;Sun, L. T.;Xie, D. Z.;Peng, S. X.;Liu, Z. W.;Zhao, H. W.;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 02A329 - 02A329-3
Publisher: IEEE
 
» A 2.5 kV Isolation 35 kV/us CMR 250 Mbps Digital Isolator in Standard CMOS With a Small Transformer Driving Technique
Abstract:
A small-size on-chip transformer-based digital isolator for power control systems is proposed. With a proposed pulse generation and detection scheme that enables a 5 V standard CMOS transistor to utilize GHz-band signals, transformer area is reduced to 1/4–1/8 that of conventional transformers. A test chip achieves a 2.5 kV isolation voltage, a 35 kV/us CMR, a 1.6 mA static current and a 250 Mbps data rate, all which are equal to or superior to those of optocouplers or conventional digital isolators. The developed technology greatly reduces the number of chips in power control systems by allowing integration of multiple isolators in a CMOS chip together with microcontrollers or gate drivers. Moreover, the high-speed low-power capability expands the application potential to include isolated serial links, controller area network (CAN), FlexRay, medical devices, displays, sensors, etc.
Autors: Kaeriyama, S.;Uchida, S.;Furumiya, M.;Okada, M.;Maeda, T.;Mizuno, M.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 435 - 443
Publisher: IEEE
 
» A 200-MHz Integrated Buck Converter With Resonant Gate Drivers for an RF Power Amplifier
Abstract:
High switching frequency dc-dc converters are present in many applications where wide regulation bandwidth and high efficiency are needed. A resonant gate driver is presented for improvement of efficiency at light-to-medium load conditions. Gate power losses that are a main contributor to total losses are reduced thanks to energy recovery. A testchip designed in 0.25- BiCMOS shows as much as a 30% decrease in power losses compared to a conventional driver at 200-MHz switching frequency. The proposed resonant gate driver is fully integrated with its inductor unlike earlier works. The limitation in the reduction of gate losses is detailed and confirmed experimentally.
Autors: Bathily, M.;Allard, B.;Hasbani, F.;
Appeared in: IEEE Transactions on Power Electronics
Publication date: Feb 2012, volume: 27, issue:2, pages: 610 - 613
Publisher: IEEE
 
» A 21 nV/ Hz Chopper-Stabilized Multi-Path Current-Feedback Instrumentation Amplifier With 2 V Offset
Abstract:
This paper describes the design of a precision instrumentation amplifier. It employs chopping to reduce its offset and noise, and the resulting ripple caused by the up-modulated offset and noise is suppressed by a ripple reduction loop. A multi-path architecture is used to eliminate the transfer function notch that would otherwise be introduced by the ripple reduction loop. The amplifier is implemented in a standard 0.7 CMOS technology and draws 143 current from a 5 V supply. Its input-referred noise is 21 nV/ Hz and its residual offset is less than 2 (12 samples). The instrumentation amplifier can also be configured as a general-purpose opamp with half the noise and offset, but which dissipates the same amount of power.
Autors: Fan, Q.;Huijsing, J. H.;Makinwa, K. A. A.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 464 - 475
Publisher: IEEE
 
» A 255 MHz Programmable Gain Amplifier and Low-Pass Filter for Ultra Low Power Impulse-Radio UWB Receivers
Abstract:
A 90 nm-CMOS power-optimized analog baseband chain for ultra-low-power impulse-radio ultra-wideband (IR-UWB) receivers is presented. The proposed device merges the functions of a programmable gain amplifier (PGA) and a low-pass filter (LPF). It consists of the cascade of three biquadratic cells made up by opamps in a series-shunt configuration, which features high input impedance, low load effects in the cascade blocks, and better frequency response. The opamp parameters are included in the overall biquad transfer function. This allows getting very low power performance, since the opamp bandwidth is not required to be much larger than the filter cutoff frequency. Moreover, the current consumption is optimized according to the selected gain level (1.3 mA at 0 dB-gain up to 1.9 mA at 40 dB-gain). The PGA features a 0–40 dB programmable gain range with a 5 dB gain-step. The LPF performs a sixth-order 255 MHz low-pass frequency response. For the overall chain the IIP3 is 14 dBm at 0 dB gain, while the input referred noise is 12.5 nV/ Hz at 40 dB gain.
Autors: D'Amico, S.;De Blasi, M.;De Matteis, M.;Baschirotto, A.;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Feb 2012, volume: 59, issue:2, pages: 337 - 345
Publisher: IEEE
 
» A 3D Monte Carlo code for the modeling of plasma dynamics and beam formation mechanism in electron cyclotron resonance ion sources
Abstract:
The code here presented is the first part of a Monte Carlo (MC) self-consistent 3D plasma simulator. It is yet able to solve the equation of motion for thousands of independent charged particles. The procedure allows to understand the consequences of each phenomenon introduced in the evolution steps of the code. MC random selection of starting parameters is used for each particles; the environmental conditions enclosed in the simulation are ECRIS magnetic field, resonant electromagnetic wave, initial plasma density distribution and MC calculation of Spitzer collision. The results of the first simulations explain some typical effects as the hollow beam formation and the main plasma deconfinement mechanism.
Autors: Neri, L.;Mascali, D.;Celona, L.;Gammino, S.;Ciavola, G.;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 02A330 - 02A330-3
Publisher: IEEE
 
» A 667 MHz Logic-Compatible Embedded DRAM Featuring an Asymmetric 2T Gain Cell for High Speed On-Die Caches
Abstract:
Circuit techniques for enhancing the retention time and random cycle of logic-compatible embedded DRAMs (eDRAMs) are presented. An asymmetric 2T gain cell utilizes the gate and junction leakages of a PMOS write device to maintain a high data ‘1’ voltage level which enables fast read access using an NMOS read device. A current-mode sense amplifier (C-S/A) featuring a cross-coupled PMOS latch and pseudo-PMOS diode pairs is proposed to overcome the innate problem of small read bit-line (RBL) voltage swing in 2T eDRAMs with improved voltage headroom and better impedance matching under process–voltage–temperature (PVT) variations. A half-swing write bit-line (WBL) scheme is adopted to improve the WBL speed by 33% and reduce its power dissipation by 25% during write-back operation with no effect on retention time. A stepped write word-line (WWL) driver reduces the current drawn from the boosted high and low supplies by 67%. A 192 kb eDRAM test chip with 512 cells-per-BL implemented in a 65 nm low-power (LP) CMOS process shows a random cycle frequency and latency of 667 MHz and 1.65 ns, respectively, at 1.1 V and 85 . The measured refresh period at a 99.9% bit yield condition was 110 which is comparable to that of recently published 1T1C eDRAM designs.
Autors: Chun, K. C.;Jain, P.;Kim, T.-H.;Kim, C. H.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 547 - 559
Publisher: IEEE
 
» A 76 GHz Multi-Layered Phased Array Antenna Using a Non-Metal Contact Metamaterial Waveguide
Abstract:
A 76 GHz phased array antenna (PAA) using waffle-iron ridge waveguides with non-metal contacts has been developed. The non-metal contact technology has the advantage of avoiding losses due to imperfect metal contacts, and also facilitates the fabrication of small-size and multi-layer stacked structures. The principle and results of the developed phase shifter, radiator and feed network are presented. For the feed network, it is shown that the phase differences between adjacent radiators are the same, which confirms the validity of the fundamental operation of the PAA. A PAA combining the feed network and 16 radiators with a size of 62 mm 62 mm 25 mm was realized. The characteristic of the PAA was evaluated by calculating the directivity using measured data from the radiator and the feed network. From these considerations, the PAA was found to have the capability of providing a beam tilt angle of while maintaining a gain of more than 32 dBi.
Autors: Kirino, H.;Ogawa, K.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2012, volume: 60, issue:2, pages: 840 - 853
Publisher: IEEE
 
» A -Band Capacitor-Coupled QVCO Using Sinusoidal Current Bias Technique
Abstract:
This study introduces an -band quadrature voltage-controlled oscillator (QVCO) based on two novel techniques: capacitor coupling and sinusoidal current biasing. The proposed QVCO achieves an excellent figure-of-merit (FOM) of 190.5 dBc/Hz. This study analyzes the properties of this QVCO, including its phase noise, oscillation frequency, and amplitude. To generate quadrature phase signals with low phase noise, the proposed design uses two capacitor-coupled LC-tank cores instead of active device—coupled cores. Sinusoidal currents through these capacitors bias the oscillator, increasing oscillation amplitude and reducing the phase noise contribution from cross-coupled transistors compared to existing QVCOs or VCOs biased with a constant current. These two techniques allow the proposed QVCO to achieve at least a theoretical 3 dB phase noise improvement compared to conventional LC-QVCOs. Implemented in a standard 0.18 m CMOS process, the proposed QVCO had a frequency tuning range of 9.2 10.4 GHz and a phase noise of 115.7 dBc/Hz@1 MHz from a carrier of 10.4 GHz while consuming 3.6 mW with 1.5 V voltage supply.
Autors: Shen, I.-S.;Jou, C. F.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 318 - 328
Publisher: IEEE
 
» A -Band Micromachined 3-D Cavity-Backed Patch Antenna Array With Integrated Diode Detector
Abstract:
A 2 2 array of -band air-dielectric cavity-backed patch antennas is presented. The array and its components are fabricated using a sequential surface micromachining technique known as the Polystrata process. Each antenna has a simulated 4.1% 10-dB return-loss bandwidth of about 94.5 GHz, a radiation efficiency of 95%, and a gain of 8.3 dB at broadside with a 76 3-dB beamwidth. The simulated gain of the entire array is 13 dB. To facilitate system integration and measurement, several methods of interface are explored, including ground–signal–ground probing, direct transition to WR-10 waveguide, and hybridly integrated detector diodes. A measured return loss of 32 dB at 94 GHz with a 10-dB bandwidth of 3.25 GHz is measured for a single antenna, and 18 dB with a 10-dB bandwidth of 4.6 GHz is measured for an array. Measured - and -plane 3-dB beamwidths of 25 are reported. Antenna pattern measurements show good correlation with simulated results. The measured broadside gain for the antenna array is 13.5 dB at 94 GHz.
Autors: Oliver, J. M.;Rollin, J.-M.;Vanhille, K.;Raman, S.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 284 - 292
Publisher: IEEE
 
» A -Band Capacitor-Coupled QVCO Using Sinusoidal Current Bias Technique
Abstract:
This study introduces an -band quadrature voltage-controlled oscillator (QVCO) based on two novel techniques: capacitor coupling and sinusoidal current biasing. The proposed QVCO achieves an excellent figure-of-merit (FOM) of 190.5 dBc/Hz. This study analyzes the properties of this QVCO, including its phase noise, oscillation frequency, and amplitude. To generate quadrature phase signals with low phase noise, the proposed design uses two capacitor-coupled LC-tank cores instead of active device—coupled cores. Sinusoidal currents through these capacitors bias the oscillator, increasing oscillation amplitude and reducing the phase noise contribution from cross-coupled transistors compared to existing QVCOs or VCOs biased with a constant current. These two techniques allow the proposed QVCO to achieve at least a theoretical 3 dB phase noise improvement compared to conventional LC-QVCOs. Implemented in a standard 0.18 m CMOS process, the proposed QVCO had a frequency tuning range of 9.2 10.4 GHz and a phase noise of 115.7 dBc/Hz@1 MHz from a carrier of 10.4 GHz while consuming 3.6 mW with 1.5 V voltage supply.
Autors: Shen, I.-S.;Jou, C. F.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 318 - 328
Publisher: IEEE
 
» A Bicriteria-Optimization-Approach-Based Dimensionality-Reduction Model for the Color Display of Hyperspectral Images
Abstract:
This paper proposes a new nonlinear dimensionality-reduction model based on a bicriteria global optimization approach for the color display of hyperspectral images. The proposed fusion model is derived from two well-known and contradictory criteria of good visualization, which are useful in any multidimensional imagery color display, namely, accuracy, with the preservation of spectral distance criterion, and contrast, guaranteeing that colors are well distinguished or concretely allowing the good separability of each observed existing material in the final visualized color image. An internal parameter allows our algorithm to express the contribution or the importance of these two criteria for a specific application. In this framework, which also can be viewed as a classical Bayesian optimization strategy involving a tradeoff between fidelity to the unreduced (raw) spectral data and the expected highly contrasted resulting mapping, we will show that a hybrid optimization strategy, combining a global and deterministic optimization procedure and a local stochastic search using the Metropolis criterion, can be exploited to efficiently minimize the complex nonlinear objective cost function related to our model. The experiments reported in this paper demonstrate that the proposed model, taking into account these two criteria of good visualization, makes easier and more reliable the interpretation and quick overview of such multidimensional hyperspectral images.
Autors: Mignotte, M.;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2012, volume: 50, issue:2, pages: 501 - 513
Publisher: IEEE
 
» A Bilinear Approach to the Position Self-Calibration of Multiple Sensors
Abstract:
This paper presents a novel algorithm for the automatic 3D localization of a set of sensors in an unknown environment. Given the measures of a set of time of arrival delays at each sensor, the approach simultaneously estimates the 3D position of the sensors and the sources that have generated the event. Such inference is obtained with no assumption about the sensor localization; the only assumption made is that the emission time of the sources must be known in order to evaluate the time of flight for each event. Moreover, we propose a further method that deals with the likely case of missing data in the measurements. This occurs when sensors are far apart or behind natural barriers that avoids the registration of the given event. Simulated experiments show the validity of the approach for different setups of sensors and number of events.
Autors: Crocco, M.;Del Bue, A.;Murino, V.;
Appeared in: IEEE Transactions on Signal Processing
Publication date: Feb 2012, volume: 60, issue:2, pages: 660 - 673
Publisher: IEEE
 
» A Biomimetic Active Electrolocation Sensor for Detection of Atherosclerotic Lesions in Blood Vessels
Abstract:
Weakly electric fish sense their surroundings in complete darkness by active electrolocation. In a biomimetic approach, we designed catheter-based technical sensor systems working according to the same biological principles that could be used for medical diagnostics of arteriosclerosis. Several measurements using artificial blood vessels, computer simulations, and a physical test bed showed that it is possible to detect and analyze vulnerable plaques in blood vessels and that our method of signal production and analysis is principally suitable for medical diagnostics.
Autors: Metzen, M.G.;Biswas, S.;Bousack, H.;Gottwald, M.G.;Mayekar, K.;von der Emde, G.;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2012, volume: 12, issue:2, pages: 325 - 331
Publisher: IEEE
 
» A Bistable Shape Memory Alloy Microvalve With Magnetostatic Latches
Abstract:
This paper presents the layout, fabrication, and characterization of a first-of-its-kind bistable shape memory microvalve. The main functional components are two counteracting shape memory alloy microbridges for switching and magnetic layers to maintain two stable switching states in power-off condition. The high demands on alignment accuracy are met by a novel fabrication process, where all components are assembled to a self-aligning valve stack. This allows full electrical, mechanical, and fluidic performance tests as well as fine adjustment of layer thicknesses prior to final bonding. The overall dimensions of first demonstrators are . Bistable operation is shown for differential pressures up to 300 kPa for gas at high flow rates of 2200 sccm. [2011-0195]
Autors: Barth, J.;Megnin, C.;Kohl, M.;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Feb 2012, volume: 21, issue:1, pages: 76 - 84
Publisher: IEEE
 
» A brief look back
Abstract:
To accommodate the lead time for publication, this column is being written at the very beginning of 2012, which makes this writer pause. ComSoc??s Wireless Communication Engineering Technologies (WCET) certification program is five years old, and it??s entering the fourth full year of semi-annual examination windows, in addition to the very first window in the Fall of 2008.
Autors: Frantz, R.;
Appeared in: IEEE Communications Magazine
Publication date: Feb 2012, volume: 50, issue:2, pages: 19 - 19
Publisher: IEEE
 
» A Broadband CMOS RF Front-End for Universal Tuners Supporting Multi-Standard Terrestrial and Cable Broadcasts
Abstract:
A wideband CMOS highly linear and low noise RF front-end including inductor-less wideband LNA, integrated passive tunable filter, harmonic rejection mixer (HRM), and loop-through amplifier (LTA) is proposed for universal tuners. The proposed inductor-less wideband LNA shows a gain range greater than 55 dB with fine gain step less than 0.5 dB while achieving higher linearity and lower noise figure (NF), as compared with the traditional resistive/active feedback LNA through a source follower (SF). The integrated tunable filter covers the entire VHF bands without dividing the frequency range by multiple filters. By adopting tunable filter and HRM simultaneously, the overall harmonic rejection ratio (HRR) of over 65 dBc is obtained. The active feedback LTA utilizing a complementary characteristic of NMOS and PMOS is proposed for supporting multiple tuner applications. The proposed RF front-end achieves a maximum voltage gain of 42 dB, a minimum NF of 4.7 dB, and CTB and CSO of under 60 dBc. The power consumption including the LTA is 144 mW at a 1.8 V supply and the chip area is 1.43 mm .
Autors: Im, D.;Kim, H.;Lee, K.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 392 - 406
Publisher: IEEE
 
» A Broadband Low-Power Low-Noise Active Balun With Second-Order Distortion Cancellation
Abstract:
This paper presents a broadband single-ended input differential output low noise amplifier exploiting IM2 cancelling. A linear feedback from the common mode output to the single-ended input effectively cancels the second-order distortion products in the differential output. The feedback path can be designed for minimum noise, leading to equal or lower noise compared to the amplifier without feedback. A replica bias ensures reduced sensitivity to process, supply voltage and temperature variations. The measured IIP2 across the band from 230 MHz to 470 MHz, varies from 19 to 26 dBm when the feedback is disabled and from 28 to 34 dBm when the feedback is enabled. Measured NF is 2.25 dB in the VHF band and between 2 and 4 dB in the UHF band. Power dissipation is 7.8 mW .
Autors: Manstretta, D.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 407 - 420
Publisher: IEEE
 
» A Broadband VHF/UHF Double-Whip Antenna
Abstract:
This paper presents a broadband VHF/UHF double-whip antenna with one lossless matching scheme combining two methods, embedded transmission line matching method and lumped-distributed hybrid matching method. By adjusting the length of the embedded transmission line, the combination of double-whip antenna and the transmission line can achieve resonance, thus realize a coarse matching. By adding a lumped-distributed hybrid matching network at the feeding point of the double-whip antenna, we can further improve the matching for the double-whip antenna. Moreover, based on the two-step matching scheme, a double-whip antenna has been designed and fabricated. Measured results show that, the VSWRs of the double-whip antenna, with the electrical lengths of and at the minimum operation frequency respectively, are less than 2 over a 17:1 octave bandwidth, and the horizontal gains of the antenna are between 4.2 dB and 6.8 dB. Thanks to its high gain, broadband and low reflection, the proposed double-whip antenna in this paper is ideal for application in vehicle wireless communication.
Autors: Ding, X.;Wang, B.-Z.;Ge, G.-D.;Wang, D.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2012, volume: 60, issue:2, pages: 719 - 724
Publisher: IEEE
 
» A capillary absorption spectrometer for stable carbon isotope ratio (13C/12C) analysis in very small samples
Abstract:
A capillary absorption spectrometer (CAS) suitable for IR laser isotope analysis of small CO2 samples is presented. The system employs a continuous-wave (cw) quantum cascade laser to study nearly adjacent rovibrational transitions of different isotopologues of CO2 near 2307 cm-1 (4.34 μm). This initial CAS system can achieve relative isotopic precision of about 10 ppm 13C, or ∼1‰ (per mil in delta notation relative to Vienna Pee Dee Belemnite) with 20–100 picomoles of entrained sample within the hollow waveguide for CO2 concentrations ∼400–750 ppm. Isotopic analyses of such gas fills in a 1-mm ID hollow waveguide of 0.8 m overall physical path length can be carried out down to ∼2 Torr. Overall 13C/12C ratios can be calibrated to ∼2‰ accuracy with diluted CO2 standards. A novel, low-cost method to reduce cw-fringing noise resulting from multipath distortions in the hollow waveguide is presented, which allows weak absorbance features to be studied at the few ppm level (peak-to-rms) after 1000 scans are co-added in ∼10 s. The CAS is meant to work directly with converted CO2 samples from a laser ablation-catalytic combustion micro-sampler to provide 13C/12C ratios of small biological isolates currently operating with spatial resolutions ∼50 μm.
Autors: Kelly, J. F.;Sams, R. L.;Blake, T. A.;Newburn, M.;Moran, J.;Alexander, M. L.;Kreuzer, H.;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 023101 - 023101-14
Publisher: IEEE
 
» A Capstone Course on Agile Software Development Using Scrum
Abstract:
In this paper, an undergraduate capstone course in software engineering is described that not only exposes students to agile software development, but also makes it possible to observe the behavior of developers using Scrum for the first time. The course requires students to work as Scrum Teams, responsible for the implementation of a set of user stories defined by a project domain expert playing the role of the Product Owner. During the course, data on project management activities are collected in order to analyze the amount of work completed, compliance with the release and iteration plans, productivity, ability in effort estimation, and the like. The paper discusses the achievement of teaching goals and provides empirical evaluation of students' progress in estimation and planning skills. A summary of lessons learned and recommendations is given, reflecting the issues to be considered when teaching courses in agile software development. Surveys of students have shown that they were overwhelmingly positive about the course, indicating that the course fully met or even exceeded their expectations.
Autors: Mahnic, V.;
Appeared in: IEEE Transactions on Education
Publication date: Feb 2012, volume: 55, issue:1, pages: 99 - 106
Publisher: IEEE
 
» A Carrier-Based PWM Strategy With Zero-Sequence Voltage Injection for a Three-Level Neutral-Point-Clamped Converter
Abstract:
Performance of a carrier-based pulsewidth modulation (CB-PWM) strategy can be improved by the inclusion of a zero-sequence voltage in the modulation-reference signal. This paper proposes a new CB-PWM strategy for a three-level neutral-point-clamped (NPC) converter, which is based on a zero-sequence voltage injection. By inclusion of the zero-sequence voltage, the sinusoidal-modulation reference is modified to 1) carry out the voltage-balancing task of the dc-link capacitors, with no additional control effort, 2) reduce the switching losses, and 3) reduce the low-frequency voltage oscillations of the neutral point. The proposed strategy is an alternative approach to the nearest three-vector (NTV) space-vector modulation (SVM) strategy and is obtained by the analysis of the NTV-SVM strategy and establishing a correlation between the NTV-SVM and the CB-PWM strategies. The salient features of the proposed scheme, as compared with the NTV-SVM strategy, are: 1) its reduced computational processing time which is attractive for digital implementation and 2) its reduced switching losses. Compared with the existing CB-PWM strategies, the proposed strategy offers 1) capability to balance the capacitor voltages and reduce the NP voltage oscillations and 2) reduced switching losses. Performance of the proposed CB-PWM strategy for a three-level NPC converter based on time-domain simulation studies in the MATLAB/SIMULINK environment is evaluated and also experimentally verified.
Autors: Pou, J.;Zaragoza, J.;Ceballos, S.;Saeedifard, M.;Boroyevich, D.;
Appeared in: IEEE Transactions on Power Electronics
Publication date: Feb 2012, volume: 27, issue:2, pages: 642 - 651
Publisher: IEEE
 
» A Cell Method Formulation of 3-D Electrothermomechanical Contact Problems With Mortar Discretization
Abstract:
A 3-D domain decomposition method for fully coupled electrothermomechanical contact problems is presented. The formulation is based on the cell method. Contacting domains are linked together by introducing a new reference frame (i.e., the mortar surface). Field discontinuities across contact interfaces are simulated by suitable constitutive operators. It is shown that the same coupling strategy can be adopted for the electrical, thermal, and mechanical contact problems. Compatibility constraints are imposed by means of dual Lagrange multipliers defined on the mortar surface. Coupled nonlinear algebraic equations are finally cast into a saddle-point problem, which is resolved by combining the Schur complement method with the Newton–Raphson method. The proposed mortar approach is validated with a commercial 3-D finite-element method multiphysics software package.
Autors: Moro, F.;Alotto, P.;Freschi, F.;Guarnieri, M.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2012, volume: 48, issue:2, pages: 503 - 506
Publisher: IEEE
 
» A Chance-Constrained Two-Stage Stochastic Program for Unit Commitment With Uncertain Wind Power Output
Abstract:
In this paper, we present a unit commitment problem with uncertain wind power output. The problem is formulated as a chance-constrained two-stage (CCTS) stochastic program. Our model ensures that, with high probability, a large portion of the wind power output at each operating hour will be utilized. The proposed model includes both the two-stage stochastic program and the chance-constrained stochastic program features. These types of problems are challenging and have never been studied together before, even though the algorithms for the two-stage stochastic program and the chance-constrained stochastic program have been recently developed separately. In this paper, a combined sample average approximation (SAA) algorithm is developed to solve the model effectively. The convergence property and the solution validation process of our proposed combined SAA algorithm is discussed and presented in the paper. Finally, computational results indicate that increasing the utilization of wind power output might increase the total power generation cost, and our experiments also verify that the proposed algorithm can solve large-scale power grid optimization problems.
Autors: Wang, Q.;Guan, Y.;Wang, J.;
Appeared in: IEEE Transactions on Power Systems
Publication date: Feb 2012, volume: 27, issue:1, pages: 206 - 215
Publisher: IEEE
 
» A Chaotic Approach of Differential Evolution Optimization Applied to Loudspeaker Design Problem
Abstract:
Over the past few years, the field of global optimization has been very active, producing different kinds of deterministic and stochastic algorithms for optimization in the continuous domain. These days, the use of evolutionary algorithms (EAs) to solve optimization problems is a common practice due to their competitive performance on complex search spaces. EAs are well known for their ability to deal with nonlinear and complex optimization problems. Differential evolution (DE) algorithms are a family of evolutionary optimization techniques that use a rather greedy and less stochastic approach to problem solving, when compared to classical evolutionary algorithms. The main idea is to construct, at each generation, for each element of the population a mutant vector, which is constructed through a specific mutation operation based on adding differences between randomly selected elements of the population to another element. Due to its simple implementation, minimum mathematical processing and good optimization capability, DE has attracted attention. This paper proposes a new approach to solve electromagnetic design problems that combines the DE algorithm with a generator of chaos sequences. This approach is tested on the design of a loudspeaker model with 17 degrees of freedom, for showing its applicability to electromagnetic problems. The results show that the DE algorithm with chaotic sequences presents better, or at least similar, results when compared to the standard DE algorithm and other evolutionary algorithms available in the literature.
Autors: Coelho, L. S.;Bora, T. C.;Lebensztajn, L.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2012, volume: 48, issue:2, pages: 751 - 754
Publisher: IEEE
 
» A Characterization of Delay Performance of Cognitive Medium Access
Abstract:
We consider a cognitive radio network where multiple secondary users (SUs) contend for spectrum usage, using random access, over available primary user (PU) channels. Our focus is on SUs' queueing delay performance, for which a systematic understanding is lacking. We take a fluid queue approximation approach to study the steady-state delay performance of SUs, for cases with a single PU channel and multiple PU channels. Using stochastic fluid models, we represent the queue dynamics as Poisson driven stochastic differential equations, and characterize the moments of the SUs' queue lengths accordingly. Since in practical systems, an SU would have no knowledge of other users' activities, its contention probability has to be set based on local information. With this observation, we develop adaptive algorithms to find the optimal contention probability that minimizes the mean queue lengths. Moreover, we study the impact of multiple channels and multiple interfaces on SUs' delay performance. As expected, the use of multiple channels and/or multiple interfaces leads to significant delay reduction. Finally, we consider packet generation control to meet the delay requirements for SUs, and develop randomized and queue-length-based control mechanisms accordingly.
Autors: Wang, Shanshan;Zhang, Junshan;Tong, Lang;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2012, volume: 11, issue:2, pages: 800 - 809
Publisher: IEEE
 
» A Circularly Polarized Ring-Antenna Fed by a Serially Coupled Square Slot-Ring
Abstract:
An aperture-coupled ring-antenna is presented in this communication. The antenna is fed by a microstrip line through a unique aperture configuration. The aperture contains a square slot ring with four short branch slots protruding toward the center of the ring. It is studied that axial-ratio and return-loss bandwidths of 8.7% centered at 2.53 GHz can be achieved. Within 2.42 GHz–2.64 GHz, the gains are all greater than 7 dBic.
Autors: Chang, T.-N.;Lin, J.-M.;Chen, Y. G.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2012, volume: 60, issue:2, pages: 1132 - 1135
Publisher: IEEE
 
» A close-coupling multi-antenna type radio frequency driven ion source
Abstract:
A newly close coupling multi-antenna type radio frequency driven ion source is tested for the purpose of essentially improving plasma coupling on the basis of our old type ion source, which reuses a NNBI (negative ion source for neutral beam injection) ion source used in 1/5th scale of the Large Helical Device NNBI. The ion source and the antenna structure are described, and the efficient plasma production in terms of the positive ion saturation current (the current density) is studied. The source is made of a metal-walled plasma chamber which is desirable from the point of view of the structural toughness for fusion and industrial application, etc. At around 160 kW of rf input power, the ion saturation current density successfully reaches the 5 A/cm2 level with a gas pressure of 0.6–2 Pa in hydrogen for 10 ms pulse duration. The rf power efficiency of the plasma production with a close coupling configuration of the antenna is improved substantially compared to that with the previous antenna unit in the old type ion source. The power efficiency is assessed as competing with that of other types of sources.
Autors: Oka, Y.;Shoji, T.;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 02B106 - 02B106-3
Publisher: IEEE
 
» A Closed-Form Expression for Estimating the Maximum Radiated Emissions From a Heatsink on a Printed Circuit Board
Abstract:
A closed-form expression is derived for determining the maximum possible radiated emissions from a heatsink over a printed circuit board or chassis plane as a function of the maximum voltage between the heatsink and plane. Two modes of radiation are considered: a patch-antenna mode and a monopole-antenna mode. The maximum emissions are the sum of the emissions due to each of these modes. Circuit board dimensions are assumed to be large compared to the heatsink dimensions. The most relevant parameters affecting the emissions are the dimensions of the heatsink. The closed-form expression is validated by comparing its results to full-wave simulation results for a variety of heatsink sizes and shapes.
Autors: He, X.;Hubing, T. H.;
Appeared in: IEEE Transactions on Electromagnetic Compatibility
Publication date: Feb 2012, volume: 54, issue:1, pages: 205 - 211
Publisher: IEEE
 
» A CMOS Noise-Squeezing Amplifier
Abstract:
Noise squeezing occurs through phase-sensitive gain implemented by a parametric process in a nonlinear LC resonator. This process enhances the sensitivity for one quadrature component of an input signal at the expense of degrading the sensitivity for the other quadrature. We demonstrate an 8.75-GHz parametric resonant amplifier in a 0.13- CMOS process, which provides gain of 21 dB and 12 dB for the two quadrature components. This 9-dB gain difference results in a 2.5-dB sensitivity improvement for one quadrature, while it degrades the other quadrature sensitivity by 6.4 dB. The amplifier bandwidth is around 800 MHz and draws 36 mA from a 1.2-V supply.
Autors: Lee, W.;Afshari, E.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2012, volume: 60, issue:2, pages: 329 - 339
Publisher: IEEE
 
» A collimator for hot plasma x-ray diagnostics in ion sources
Abstract:
We present a collimator configuration for measuring energy resolved x-ray plasma volume bremsstrahlung emitted, e.g., by an ECRIS. Special attention we paid to shielding the detector against interfering Compton scattered radiation and wall bremsstrahlung stemming from the collimator entrance aperture. We estimate the efficiency for shielding of Compton scattered radiation at least attainable by this arrangement.
Autors: Bernhardi, K.;Wiesemann, K.;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 02A337 - 02A337-3
Publisher: IEEE
 
» A Combined Position and Stator-Resistance Observer for Salient PMSM Drives: Design and Stability Analysis
Abstract:
A reduced-order position observer with stator-resistance adaptation is proposed for motion-sensorless permanent-magnet synchronous motor drives. A general analytical solution for the stabilizing observer gain and stability conditions for the stator-resistance adaptation are derived. Under these conditions, the local stability of the position and stator-resistance estimation is guaranteed at every operating point except the zero frequency, if other motor parameters are known. Furthermore, the effect of inaccurate model parameters on the local stability of the position estimation is studied, and an observer gain design that makes the observer robust is proposed. The proposed observer is experimentally tested using a 2.2-kW motor drive; stable operation at very low speeds under different loading conditions is demonstrated.
Autors: Hinkkanen, M.;Tuovinen, T.;Harnefors, L.;Luomi, J.;
Appeared in: IEEE Transactions on Power Electronics
Publication date: Feb 2012, volume: 27, issue:2, pages: 601 - 609
Publisher: IEEE
 
» A Compact Capacitor-Less High-Speed DRAM Using Field Effect-Controlled Charge Regeneration
Abstract:
We demonstrate experimentally a capacitor-less one-transistor dynamic random access memory (DRAM) based on fully depleted silicon-on-insulator substrate. In our device, the charges are directly stored in front gate capacitor and read out through a fast feedback regeneration process. The simulated read/write times of our device reach below 1 ns, much faster than conventional 1T-1C DRAM. The read/write biasing voltages can be scaled down to 1.1 V, achieving long retention time .
Autors: Wan, J.;Le Royer, C.;Zaslavsky, A.;Cristoloveanu, S.;
Appeared in: IEEE Electron Device Letters
Publication date: Feb 2012, volume: 33, issue:2, pages: 179 - 181
Publisher: IEEE
 
» A Compact Dynamic-Performance-Improved Current-Steering DAC With Random Rotation-Based Binary-Weighted Selection
Abstract:
Conventional binary-weighted current-steering DACs are generally operated with current groups where each group is binary-weighted and formed with predetermined members of a unit current-source array. This paper proposes a random rotation-based binary-weighted selection (RRBS) that efficiently performs dynamic-element matching (DEM) by randomly rotating the sequence of these units to form new binary-weighted current groups for each DAC output. Without using binary-to-thermometer decoders, RRBS features its simplicity and compactness of DEM realization. Compared to conventional binary-weighted DACs, RRBS DACs are insensitive to the mismatch of small-size current-sources and exhibit better dynamic performance. A 10-bit RRBS DAC is implemented with only 0.034 mm in a standard 1P6M 1.8 V 0.18 m CMOS process. Measured performance achieves 61 dB spurious-free dynamic range (SFDR) in the Nyquist bandwidth with 500 MS/s, while its active area is less than one-tenth of that required by state-of-the-art 10-bit current steering DACs. To the best of our knowledge, the proposed RRBS implements the smallest area for high-speed current-steering DACs up to now. Its SFDR is also comparable to that of 12-bit published designs. Three popular figures-of-merit (FOMs) are used to compare this design with other state-of-the-art 10–12-bit DACs, with the proposed design performing best with 2 FOMs.
Autors: Lin, W.-T.;Kuo, T.-H.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Feb 2012, volume: 47, issue:2, pages: 444 - 453
Publisher: IEEE
 
» A Compact Manually Actuated Micromanipulator
Abstract:
This letter reports a compact, versatile, and user-friendly micromanipulator that uses an elastically deformable silicon microtweezer to grab microentities, and a micrometer head for rotational manual actuation. The micro-/macroconnection is achieved via a graphite interface that results in a compact and portable design and placement on most translation stages. The system which can operate in both air and liquid, and transport objects between the two media, has a wide range of applications. We demonstrate but a few of them, including in situ construction of microstructures in 3-D, isolation and placement of individual microparticles on designated spots on sensors, on-demand microcontact printing of microparticles, and manipulation of live stem cell spheres. [2011-0237]
Autors: Chan, B.-D.;Mateen, F.;Chang, C.-L.;Icoz, K.;Savran, C. A.;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Feb 2012, volume: 21, issue:1, pages: 7 - 9
Publisher: IEEE
 
» A compact neutron generator using a field ionization source
Abstract:
Field ionization as a means to create ions for compact and rugged neutron sources is pursued. Arrays of carbon nano-fibers promise the high field-enhancement factors required for efficient field ionization. We report on the fabrication of arrays of field emitters with a density up to 106 tips/cm2 and measure their performance characteristics using electron field emission. The critical issue of uniformity is discussed, as are efforts towards coating the nano-fibers to enhance their lifetime and surface properties.
Autors: Persaud, Arun;Waldmann, Ole;Kapadia, Rehan;Takei, Kuniharu;Javey, Ali;Schenkel, Thomas;
Appeared in: Review of Scientific Instruments
Publication date: Feb 2012, volume: 83, issue:2, pages: 02B312 - 02B312-4
Publisher: IEEE
 

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