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9661-9680hit(42807hit)

  • IDDQ Outlier Screening through Two-Phase Approach: Clustering-Based Filtering and Estimation-Based Current-Threshold Determination

    Michihiro SHINTANI  Takashi SATO  

     
    PAPER-Dependable Computing

      Vol:
    E97-D No:8
      Page(s):
    2095-2104

    We propose a novel IDDQ outlier screening flow through a two-phase approach: a clustering-based filtering and an estimation-based current-threshold determination. In the proposed flow, a clustering technique first filters out chips that have high IDDQ current. Then, in the current-threshold determination phase, device-parameters of the unfiltered chips are estimated based on measured IDDQ currents through Bayesian inference. The estimated device-parameters will further be used to determine a statistical leakage current distribution for each test pattern and to calculate a and suitable current-threshold. Numerical experiments using a virtual wafer show that our proposed technique is 14 times more accurate than the neighbor nearest residual (NNR) method and can achieve 80% of the test escape in the case of small leakage faults whose ratios of leakage fault sizes to the nominal IDDQ current are above 40%.

  • A QoS-Aware Differential Processing Control Scheme for OpenFlow-Based Mobile Networks

    Yeunwoong KYUNG  Taihyong YIM  Taekook KIM  Tri M. NGUYEN  Jinwoo PARK  

     
    LETTER-Information Network

      Vol:
    E97-D No:8
      Page(s):
    2178-2181

    This paper proposes a QoS-aware differential processing control (QADPC) scheme for OpenFlow-based mobile networks. QADPC classifies the input packets to the control plane by considering end terminal mobility and service type. Then, different capacities are assigned to each classified packet for prioritized processing. By means of Markov chains, QADPC is evaluated in terms of blocking probability and waiting time in the control plane. Analytical results demonstrate that QADPC offers high priority packets both lower blocking probability and less waiting time.

  • A Variable-Supply-Voltage 60-GHz PA with Consideration of HCI Issues for TDD Operation

    Rui WU  Yuuki TSUKUI  Ryo MINAMI  Kenichi OKADA  Akira MATSUZAWA  

     
    PAPER-Electronic Circuits

      Vol:
    E97-C No:8
      Page(s):
    803-812

    A 60-GHz power amplifier (PA) with a reliability consideration for a hot-carrier-induced~(HCI) degradation is presented. The supply voltage of the last stage of the PA ($V_{{ m PA}}$) is dynamically controlled by an on-chip digitally-assisted low drop-out voltage regulator (LDO) to alleviate HCI effects. A physical model for estimation of HCI degradation of NMOSFETs is discussed and investigated for dynamic operation. The PA is fabricated in a standard 65-nm CMOS process with a core area of 0.21,mm$^{2}$, which provides a saturation power of 10.1,dBm to 13.2,dBm with a peak power-added efficiency~(PAE) of 8.1% to 15.0% for the supply voltage $V_{{ m PA}}$ which varies from 0.7,V to 1.0,V at 60,GHz, respectively.

  • FOREWORD Open Access

    Haris GACANIN  

     
    FOREWORD

      Vol:
    E97-B No:8
      Page(s):
    1493-1493
  • Optimal Power Allocation and Outage Analysis for Cognitive MIMO Full Duplex Relay Network Based on Orthogonal Space-Time Block Codes

    Ying ZHU  Jia LIU  Zhiyong FENG  Ping ZHANG  

     
    PAPER

      Vol:
    E97-B No:8
      Page(s):
    1567-1576

    This paper investigates power allocation and outage performance for the MIMO full duplex relaying (MFDR) based on orthogonal space-time block Codes (OSTBC) in cognitive radio systems. OSTBC transmission is used as a simple way to obtain multi-antenna diversity gain. Cognitive MFDR systems offer the advantage not only of increasing spectral efficiency by spectrum sharing but also of extending the coverage through the use of relays. In cognitive MFDR systems, the primary user experiences interference from the secondary source and relay simultaneously due to the full duplexing. What is therefore needed is a way to optimize the transmission powers at the secondary source and relay. Therefore, we propose an optimal power allocation (OPA) scheme based on minimizing the outage probability in cognitive MFDR systems. We then analyze the outage probability of the secondary user in the noise-limited and interference-limited environments under Nakagami-m fading channels. Simulation results show that the proposed schemes achieve performance improvement in terms of outage probability.

  • Mobility Overlap-Removal-Based Leakage Power and Register-Aware Scheduling in High-Level Synthesis

    Nan WANG  Song CHEN  Wei ZHONG  Nan LIU  Takeshi YOSHIMURA  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E97-A No:8
      Page(s):
    1709-1719

    Scheduling is a key problem in high level synthesis, as the scheduling results affect most of the important design metrics. In this paper, we propose a novel scheduling method to simultaneously optimize the leakage power of functional units with dual-Vth techniques and the number of registers under given timing and resource constraints. The mobility overlaps between operations are removed to eliminate data dependencies, and a simulated-annealing-based method is introduced to explore the mobility overlap removal solution space. Given the overlap-free mobilities, the resource usage and register usage in each control step can be accurately estimated. Meanwhile, operations are scheduled so as to optimize the leakage power of functional units with minimal number of registers. Then, a set of operations is iteratively selected, reassigned as low-Vth, and rescheduled until the resource constraints are all satisfied. Experimental results show the efficiency of the proposed algorithm.

  • Tracking Analysis of Adaptive Filters with Error and Matrix Data Nonlinearities

    Wemer M. WEE  Isao YAMADA  

     
    PAPER-Digital Signal Processing

      Vol:
    E97-A No:8
      Page(s):
    1659-1673

    We consider a unified approach to the tracking analysis of adaptive filters with error and matrix data nonlinearities. Using energy-conservation arguments, we not only derive earlier results in a unified manner, but we also obtain new performance results for more general adaptive algorithms without requiring the restriction of the regression data to a particular distribution. Numerical simulations support the theoretical results.

  • Fast Correlation Method for Partial Fourier and Hadamard Sensing Matrices in Matching Pursuit Algorithms

    Kee-Hoon KIM  Hosung PARK  Seokbeom HONG  Jong-Seon NO  

     
    PAPER-Digital Signal Processing

      Vol:
    E97-A No:8
      Page(s):
    1674-1679

    There have been many matching pursuit algorithms (MPAs) which handle the sparse signal recovery problem, called compressed sensing (CS). In the MPAs, the correlation step makes a dominant computational complexity. In this paper, we propose a new fast correlation method for the MPA when we use partial Fourier sensing matrices and partial Hadamard sensing matrices which are widely used as the sensing matrix in CS. The proposed correlation method can be applied to almost all MPAs without causing any degradation of their recovery performance. Also, the proposed correlation method can reduce the computational complexity of the MPAs well even though there are restrictions depending on a used MPA and parameters.

  • Complex-Valued Bipartite Auto-Associative Memory

    Yozo SUZUKI  Masaki KOBAYASHI  

     
    PAPER-Nonlinear Problems

      Vol:
    E97-A No:8
      Page(s):
    1680-1687

    Complex-valued Hopfield associative memory (CHAM) is one of the most promising neural network models to deal with multilevel information. CHAM has an inherent property of rotational invariance. Rotational invariance is a factor that reduces a network's robustness to noise, which is a critical problem. Here, we proposed complex-valued bipartite auto-associative memory (CBAAM) to solve this reduction in noise robustness. CBAAM consists of two layers, a visible complex-valued layer and an invisible real-valued layer. The invisible real-valued layer prevents rotational invariance and the resulting reduction in noise robustness. In addition, CBAAM has high parallelism, unlike CHAM. By computer simulations, we show that CBAAM is superior to CHAM in noise robustness. The noise robustness of CHAM decreased as the resolution factor increased. On the other hand, CBAAM provided high noise robustness independent of the resolution factor.

  • Evaluation of Maximum Redundancy of Data Compression via Substring Enumeration for k-th Order Markov Sources

    Ken-ichi IWATA  Mitsuharu ARIMURA  Yuki SHIMA  

     
    PAPER-Information Theory

      Vol:
    E97-A No:8
      Page(s):
    1754-1760

    Dubé and Beaudoin proposed a lossless data compression called compression via substring enumeration (CSE) in 2010. We evaluate an upper bound of the number of bits used by the CSE technique to encode any binary string from an unknown member of a known class of k-th order Markov processes. We compare the worst case maximum redundancy obtained by the CSE technique for any binary string with the least possible value of the worst case maximum redundancy obtained by the best fixed-to-variable length code that satisfies the Kraft inequality.

  • Performance Analysis of Multiuser Relay Networks with Feedback Delay

    Jie YANG  Xiaofei ZHANG  Kai YANG  

     
    PAPER-Communication Theory and Signals

      Vol:
    E97-A No:8
      Page(s):
    1770-1779

    In this paper, we analyze the performance of a dual-hop multiuser amplify-and-forward (AF) relay network with the effect of the feedback delay, where the source and each of the K destinations are equipped with Nt and Nr antennas respectively, and the relay is equipped with a single antenna. In the relay network, multi-antenna and multiuser diversities are guaranteed via beamforming and opportunistic scheduling, respectively. To examine the impact of delayed feedback, the new exact analytical expressions for the outage probability (OP) and symbol error rate (SER) are derived in closed-form over Rayleigh fading channel, which are useful for a large number of modulation schemes. In addition, we present the asymptotic expressions for OP and SER in the high signal-to-noise ratio (SNR) regime, from which we gain an insight into the system performance with deriving the diversity order and array gain. Moreover, based on the asymptotic expressions, we determine power allocation among the network nodes such that the OP is minimized. The analytical expressions are validated by Monte-Carlo simulations.

  • Block-Refined Orthogonal Matching Pursuit for Sparse Signal Recovery

    Ying JI  Xiaofu WU  Jun YAN  Wei-ping ZHU  Zhen YANG  

     
    LETTER-Digital Signal Processing

      Vol:
    E97-A No:8
      Page(s):
    1787-1790

    We propose a variant of OMP algorithm named BROMP for sparse solution. In our algorithm, the update rule of MP algorithm is employed to reduce the number of least square calculations and the refining strategy is introduced to further improve its performance. Simulations show that the proposed algorithm performs better than the OMP algorithm with significantly lower complexity.

  • Revocable Identity-Based Encryption with Rejoin Functionality

    Jae Hong SEO  Keita EMURA  

     
    LETTER-Cryptography and Information Security

      Vol:
    E97-A No:8
      Page(s):
    1806-1809

    In the Identity-Based Encryption (IBE) setting, the rejoin functionality seems to be impossible since each user has the unique identity as its public key. Moreover, sometimes these identities are unchangeable, e.g., biological information (finger print iris, and so on) is regarded as the identity. Even if changeable value is indicated as an identity, e.g., e-mail address, it is preferable that the same identity can be used after a secret key is leaked. In this paper, we give a formal security definition of RIBE with the rejoin functionality, and also show that the Seo-Emura RIBE scheme [PKC 2013] (with a slight modification) has the rejoin functionality.

  • Power Line Communications: Understanding the Channel for Physical Layer Evolution Based on Filter Bank Modulation Open Access

    Andrea M. TONELLO  Alberto PITTOLO  Mauro GIROTTO  

     
    INVITED PAPER

      Vol:
    E97-B No:8
      Page(s):
    1494-1503

    This paper provides an overview of power line communication (PLC) applications, challenges and possible evolution. Emphasis is put on two relevant aspects: a) channel characterization and modeling, b) filter bank modulation for spectral efficient transmission. The main characteristics of both the indoor channel (in-home, in-ship, in-car) and the outdoor low voltage and medium voltage channels are reported and compared. A simple approach to statistically model the channel frequency response (CFR) is described and it is based on the generation of a vector of correlated random variables. To overcome the channel distortions, it is shown that filter bank modulation can provide robust performance. In particular, it is shown that the sub-channel spectral containment of filtered multitone modulation (FMT) can provide high notching capability and spectral efficiency. Reduced complexity can be obtained with a cyclic filter bank modulation approach that we refer to as cyclic block FMT modulation (CB-FMT) which still provides higher spectral flexibility/efficiency than OFDM.

  • Broadband Access in Complex Environments: LTE on Railway Open Access

    César BRISO-RODRÍGUEZ  Carlos F. LÓPEZ  Jean R.O. FERNÁNDEZ  Sergio PÉREZ  Drasko DRASKOVIC  Jaime CALLE-SÁNCHEZ  Mariano MOLINA-GARCIA  José I. ALONSO  Carlos RODRÍGUEZ  Carlos HERNÁNDEZ  Juan MORENO  José RODRÍGUEZ-PIÑEIRO  José A. GARCÍA-NAYA  Luis CASTEDO  Alfonso FERNANDEZ-DURÁN  

     
    INVITED PAPER

      Vol:
    E97-B No:8
      Page(s):
    1514-1527

    This paper assesses the main challenges associated with the propagation and channel modeling of broadband radio systems in a complex environment of high speed and metropolitan railways. These challenges comprise practical simulation, modeling interferences, radio planning, test trials and performance evaluation in different railway scenarios using Long Term Evolution (LTE) as test case. This approach requires several steps; the first is the use of a radio propagation simulator based on ray-tracing techniques to accurately predict propagation. Besides the radio propagation simulator, a complete test bed has been constructed to assess LTE performance, channel propagation conditions and interference with other systems in real-world environments by means of standard-compliant LTE transmissions. Such measurement results allowed us to evaluate the propagation and performance of broadband signals and to test the suitability of LTE radio technology for complex railway scenarios.

  • Anatomy of a Digital Coherent Receiver Open Access

    Robert BORKOWSKI  Darko ZIBAR  Idelfonso TAFUR MONROY  

     
    INVITED PAPER

      Vol:
    E97-B No:8
      Page(s):
    1528-1536

    Digital coherent receivers have gained significant attention in the last decade. The reason for this is that coherent detection, along with digital signal processing (DSP) allows for substantial increase of the channel capacity by employing advanced detection techniques. In this paper, we first review coherent detection technique employed in the receiver as well as the required receiver structure. Subsequently, we describe the core part of the receiver — DSP algorithms — that are used for data processing. We cover all basic elements of a conventional coherent receiver DSP chain: deskew, orthonormaliation, chromatic dispersion compensation/nonlinear compensation, resampling and timing recovery, polarization demultiplexing and equalization, frequency and phase recovery, digital demodulation. We also describe novel subsystems of a digital coherent receiver: modulation format recognition and impairment mitigation via expectation maximization, which may gain popularity with increasing importance of autonomous networks.

  • Wireless and Wireline Service Convergence in Next Generation Optical Access Networks — The FP7 WISCON Project

    J. J. VEGAS OLMOS  X. PANG  A. LEBEDEV  M. SALES  I. TAFUR MONROY  

     
    PAPER

      Vol:
    E97-B No:8
      Page(s):
    1537-1546

    The next generation of information technology demands both high capacity and mobility for applications such as high speed wireless access capable of supporting broadband services. The transport of wireless and wireline signals is converging into a common telecommunication infrastructure. In this paper, we will present the Marie Curie Framework Program 7 project “Wireless and wireline service convergence in next generation optical access networks” (WISCON), which focuses on the conception and study of novel architectures for wavelength-division-multiplexing (WDM) optical multi-modulation format radio-over-fiber (RoF) systems; this is a promising solution to implement broadband seamless wireless -wireline access networks. This project successfully concluded in autumn 2013, and is being follow up by another Marie Curie project entitled “flexible edge nodes for dynamic optical interconnection of access and core networks” (FENDOI), which will be also briefly described.

  • A Queueing Model of a Multi-Service System with State-Dependent Distribution of Resources for Each Class of Calls

    Slawomir HANCZEWSKI  Maciej STASIAK  Joanna WEISSENBERG  

     
    PAPER

      Vol:
    E97-B No:8
      Page(s):
    1592-1605

    This paper presents a new, accurate multi-service model of a queueing system with state-dependent distribution of resources for each class of calls. The analysis of the considered queueing system was carried out at both the microstate and macrostate levels. The proposed model makes it possible to evaluate averaged parameters of queues for individual classes of calls that are offered to the system. In addition, the paper proposes a new algorithm for a determination of the occupancy distribution in the queueing system at the microstate level. The results of the calculations are compared with the results of a digital simulation for multi-service queueing systems with state-independent distribution of resources.

  • Effective PPS Signal Generation with Predictive Synchronous Loop for GPS

    YanBin ZHANG  WeiJun LU  DengYun LEI  YongCan HUANG  DunShan YU  

     
    PAPER-Navigation, Guidance and Control Systems

      Vol:
    E97-B No:8
      Page(s):
    1742-1749

    The Global Position System (GPS), which is well known as a global tool for positioning, is also the primary system for time transfer. GPS can deliver very precise time to every corner of the world. Usually, a GPS receiver indicates the precise time by means of the 1PPS (one pulse per second) signal. This paper studies the precise time transfer system structure of GPS receivers and then proposes an effective PPS signal generation method with predictive synchronous loop, combining phase error prediction and dynamic threshold adjustment. A GPS time transfer system is implemented and measured in detail to demonstrate the validity of the proposed algorithm. Assuming the receiver clock rate of 16.368MHz, the proposed method can achieve the accuracy of ±20ns in the scope 1δ which can meet the requirements of the vast majority of occasions. Through a long period of testing, we prove the feasibility of this algorithm experimentally.

  • Tunable Resonator Employing Comb-shaped Transmission Line and Semiconductor Switches

    Kunihiro KAWAI  Daisuke KOIZUMI  Hiroshi OKAZAKI  Shoichi NARAHASHI  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E97-C No:8
      Page(s):
    795-802

    This paper presents a simple-structured tunable resonator employing semiconductor switches that can change its resonant frequency discretely but precisely. The tunable resonator comprises a transmission line with a comb-shaped pattern and multiple single-pole single-throw (SPST) switches placed between the teeth of the comb-shaped pattern. The resonator changes its resonant frequency according to the switch states, by controlling the path length carrying a high frequency current. The characteristics of the proposed resonator are evaluated through both method of moment electromagnetic simulation and fabrication, using GaAs FET SPST switches. The fabricated resonator changes its resonant frequency from 1.63,GHz to 1.85,GHz. This paper also introduces two circuit designs based on the proposed resonator that expands the tuning range of the resonant frequency or the number of resonant frequencies to be obtained.

9661-9680hit(42807hit)