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[Keyword] SI(16314hit)

11501-11520hit(16314hit)

  • Predictive Geometry Compression of 3-D Mesh Models Using a Joint Prediction

    Jeong-Hwan AHN  Yo-Sung HO  

     
    LETTER-Multimedia Systems

      Vol:
    E85-B No:12
      Page(s):
    2966-2970

    In this letter, we address geometry coding of 3-D mesh models. Using a joint prediction, the encoder predicts vertex positions in the layer traversal order. After we apply the joint prediction algorithm to eliminate redundancy among vertex positions using both position and angle values of neighboring triangles, we encode those prediction errors using a uniform quantizer and an entropy coder. The proposed scheme demonstrates improved coding efficiency for various VRML test data.

  • Performance Improvement of OFDM System with Consideration on the Characteristics of Power-Line Noise

    Kazutoshi SUGIMOTO  Hiraku OKADA  Takaya YAMAZATO  Masaaki KATAYAMA  

     
    PAPER

      Vol:
    E85-A No:12
      Page(s):
    2822-2829

    In narrow band power-line communication (PLC) systems, which use frequency band below a few hundred kHz, the noise on power-line is non-white and non-stationary. Under such environment, the performance of Orthogonal Frequency Division Multiplex (OFDM) modulation system is analyzed, and time and frequency dependence of bit error rate (BER) is clarified. In addition, the possibility of performance improvement with the symbol level repetition coding employing cyclo-stationary feature of power-line noise is presented.

  • A Simplified Dopant Pile-Up Model for Process Simulators

    Hirokazu HAYASHI  Noriyuki MIURA  Hirotaka KOMATSUBARA  Marie MOCHIZUKI  Koichi FUKUDA  

     
    PAPER-Semiconductor Materials and Devices

      Vol:
    E85-C No:12
      Page(s):
    2117-2122

    This paper describes an effective model which reproduces the dependence on the source/drain (S/D) process of the reverse short channel effect (RSCE) of the MOSFET threshold voltage (Vth). It is useful for local modeling which is effective within the limited process conditions. The proposed model is based on the physics where the key factor of RSCE is the dopant pile-up in the Si/SiO2 interface. The purpose of the model is for TCAD to be put to actual use as a quick solution tool. The calculation cost is much lower than a pair diffusion model, because the model is implemented in a conventional process simulator that solves one equation for each impurity. The capability of the simplified model is investigated for the dependence of various process conditions on the RSCE. Using our model, we also report the application of both the actual n-channel and p-channel MOSFETs.

  • A Software Radio Receiver with Direct Conversion and Its Digital Processing

    Robert MORELOS-ZARAGOZA  Shinichiro HARUYAMA  Masayoshi ABE  Noboru SASHO  Lachlan B. MICHAEL  Ryuji KOHNO  

     
    PAPER

      Vol:
    E85-B No:12
      Page(s):
    2741-2749

    This paper discusses a design methodology suitable for the development of software defined radio platforms. A flexible digital receiver was designed and implemented using a multi-port direct converter and an FPGA-based platform. The design starts with a hardware-oriented top-level system model. The model is built based on basic signal processing blocks connected together in a graphical tool. Carrier symbol timing recovery is implemented in the discrete-time (digital) domain with an interpolator-based synchronizer. Carrier phase and frequency are recovered using a feedback synchronization algorithm (a second-order type-II digital PLL). Experimental results of the platform and its simulation results demonstrate the effectiveness of the proposed design methodology.

  • Numerical Analysis of Nonlinear Distortion Generated from a Single Varactor and an Anti-Series Varactor Pair

    Masami AKAIKE  Takashi OHIRA  Keizo INAGAKI  Qing HAN  

     
    PAPER

      Vol:
    E85-C No:12
      Page(s):
    1990-1999

    Higher-order harmonics and distortions generated by nonlinearity of capacitance-voltage characteristic of a single varactor and an anti-series-connected varactor pair are analyzed and compared. The effect of linear and parabolic terms of nonlinearity to harmonics outputs and distortions is discussed. It is shown that an anti-series-connected varactor pair has a completely suppressed linear term and reduced parabolic term. The advantage of an anti-series-connected varactor pair is theoretically explained.

  • Small Protrusion Used as a Probe for Apertureless Scanning Near-Field Optical Microscopy

    Noritaka YAMAMOTO  Takashi HIRAGA  

     
    LETTER

      Vol:
    E85-C No:12
      Page(s):
    2104-2108

    We demonstrated apertureless scanning near-field optical microscopy using a small protrusion (a simple 500-nm-diameter polystyrene particle) on a flat glass substrate as a probe. We designed a small sample stage to operate with the particle probe. It is a 40-µm-diameter circular stage, fabricated from an optical fiber by Hydrofluoric acid (HF) etching. In this paper, we present the first atomic force microscope and scanning near-field optical microscope images obtained with such a probe. We also discuss schemes for probe-sample distance control in this novel form of apertureless scanning near-field optical microscopy.

  • A Genetic Algorithm for the Minimization of OPKFDDs

    Migyoung JUNG  Gueesang LEE  Sungju PARK  Rolf DRECHSLER  

     
    LETTER-VLSI Design Technology and CAD

      Vol:
    E85-A No:12
      Page(s):
    2943-2945

    OPKFDDs (Ordered Pseudo-Kronecker Functional Decision Diagrams) are a data structure that provides compact representation of Boolean functions. The size of OPKFDDs depends on a variable ordering and on decomposition type choices. Finding an optimal representation is very hard and the size of the search space is n! 32n-1, where n is the number of input variables. To overcome the huge search space of the problem, a genetic algorithm is proposed for the generation of OPKFDDs with minimal number of nodes.

  • A Compiler Generation Method for HW/SW Codesign Based on Configurable Processors

    Shinsuke KOBAYASHI  Kentaro MITA  Yoshinori TAKEUCHI  Masaharu IMAI  

     
    PAPER-Hardware/Software Codesign

      Vol:
    E85-A No:12
      Page(s):
    2586-2595

    This paper proposes a compiler generation method for PEAS-III (Practical Environment for ASIP development), which is a configurable processor development environment for application domain specific embedded systems. Using the PEAS-III system, not only the HDL description of a target processor but also its target compiler can be generated. Therefore, execution cycles and dynamic power consumption can be rapidly evaluated. Two processors and their derivatives were designed using the PEAS-III system in the experiment. Experimental results show that the trade-offs among area, performance and power consumption of processors were analyzed in about twelve hours and the optimal processor was selected under the design constraints by using generated compilers and processors.

  • A Compact Wideband T/R Switching Circuit Utilizing Quadrature Couplers and Gate-and-Drain-Driven HPAs

    Hiromitsu UCHIDA  Masatoshi NII  Norio TAKEUCHI  Yoshihiro TSUKAHARA  Moriyasu MIYAZAKI  Yasushi ITOH  

     
    PAPER

      Vol:
    E85-C No:12
      Page(s):
    2022-2028

    A novel compact T/R (Transmit/Receive) switching circuit for wideband T/R modules has been proposed. It employs quadrature couplers and gate-and-drain-driven HPAs to remove circulators or T/R switches from a conventional T/R module, and T/R switching is made with controlling biasing conditions of the FETs in HPAs. Furthermore, an optimum biasing condition and design of output matching circuit of the HPA have been studied to reduce loss in RX-mode, and the validity of the method has been confirmed by measurements.

  • Differential Constant Modulus Algorithm for Anchored Blind Equalization of AR Channels

    Teruyuki MIYAJIMA  

     
    LETTER-Digital Signal Processing

      Vol:
    E85-A No:12
      Page(s):
    2939-2942

    A blind equalizer which uses the differential constant modulus algorithm (DCMA) is introduced. An anchored FIR equalizer applied to a first-order autoregressive channel and updated according to the DCMA is shown to converge to the inverse of that channel regardless of the initial tap-weights and the gain along the direct path.

  • Locally Optimum Rank Detector Test Statistics for Composite Signals in Generalized Observations: One-Sample Case

    Jinsoo BAE  Iickho SONG  

     
    LETTER-Fundamental Theories

      Vol:
    E85-B No:11
      Page(s):
    2509-2511

    The one-sample locally optimum rank detector test statistics for composite signals in multiplicative and signal-dependent noise are obtained. Since the one-sample locally optimum rank detector makes use of the sign statistics of observations as well as the rank statistics, both 'even' and 'odd' score functions have to be considered. Although the one-sample locally optimum rank detector requires two score functions while the two-sample detector requires only one score function, the one-sample detector requires fewer calculations since it has to rank fewer observations.

  • Radio Multi-Path Propagation Measurement and Analysis at 2.4 GHz at Roadside

    Jongtaek OH  

     
    LETTER-Antenna and Propagation

      Vol:
    E85-B No:11
      Page(s):
    2551-2553

    Short range communication between roadside equipment and on-board equipment is very important for ITS (Intelligent Transport System). In this paper, for reliable roadside communication, the radio multi-path propagation at 2.4 GHz at roadside was measured and analyzed.

  • MPEG-2 Error Concealment over Burst-Packet-Loss Networks

    Shih-Hsuan YANG  Jia-Ming LIN  

     
    LETTER-Vision

      Vol:
    E85-A No:11
      Page(s):
    2557-2560

    In this letter, we propose a two-stage object-based error-concealment technique for MPEG-2 video transmitted in a burst-packet-loss environment. A burst packet loss typically destroys a large area of MPEG-2 coded video. In the first stage, the missing area is intra-picture estimated and concealed in terms of a region-based approach. In the second stage, irregular-moving objects with respect to the background are identified and compensated from the predictive picture. As compared with conventional concealment approaches, the proposed method achieves better PSNR performance and reduces the visual artifacts.

  • Locally Optimum Rank Detector Test Statistics for Composite Signals in Generalized Observations: Two-Sample Case

    Jinsoo BAE  Sun Yong KIM  

     
    LETTER-Fundamental Theories

      Vol:
    E85-B No:11
      Page(s):
    2512-2514

    The two-sample locally optimum rank detector test statistics for composite signals in additive, multiplicative, and signal-dependent noise are obtained in this letter. Compared with the structure of the one-sample locally optimum rank detector, that of the two-sample locally optimum rank detector is shown to be simpler, although it needs more computations. It is known that there is a trade-off of computational complexity and structural simplicity between the one- and two-sample detectors.

  • An Efficient Algorithm for Finding All DC Solutions of Piecewise-Linear Circuits

    Kiyotaka YAMAMURA  Masaki SATO  Osamu NAKAMURA  Takayoshi KUMAKURA  

     
    PAPER-Nonlinear Problems

      Vol:
    E85-A No:11
      Page(s):
    2459-2467

    An efficient algorithm is proposed for finding all dc solutions of piecewise-linear (PWL) circuits. This algorithm is based on a powerful test (termed the LP test) for nonexistence of a solution to a system of PWL equations in a given region using the dual simplex method. The proposed algorithm also uses a special technique that decreases the number of regions on which the LP test is performed. By numerical examples, it is shown that the proposed algorithm could find all solutions of large scale problems, including those where the number of variables is 500 and the number of linear regions is 10500, in practical computation time.

  • A Planar Cross-Junction Power Divider for the Center Feed in Single-Layer Slotted Waveguide Arrays

    Se-Hyun PARK  Jiro HIROKAWA  Makoto ANDO  

     
    PAPER-Antenna and Propagation

      Vol:
    E85-B No:11
      Page(s):
    2476-2481

    The authors propose a novel 3-way power divider named a planar cross-junction, which is used as the center feed for single-layer slotted waveguide arrays. A feeding waveguide consisting of a cascade connection of these dividers is placed at the middle of radiating waveguide in a single layer. The length of radiating waveguides is halved; the long line effect in traveling wave operation is halved and bandwidth is widened. One divider as a unit is designed by Galerkin's method of moments to suppress the reflection and to control the amplitude and the phase of the divided power into two radiating waveguides on both sides of a feed one. Two types of the cross-junction with a different divided power ratio are designed and tested by experiments in 4 GHz band. The mutual coupling effects between two adjacent cross-junctions as cascaded in a feeding waveguide of the array are predicted to be small enough; units designed here are directly applicable for a multiple-way power divider.

  • Low-Temperature Gate Insulator for Poly-Si Thin Film Transistors by Combination of Photo-Oxidation and Plasma Enhanced Chemical Vapor Deposition Using Tetraethylorthosilicate and O2 Gases

    Yukihiko NAKATA  Tetsuya OKAMOTO  Toshimasa HAMADA  Takashi ITOGA  Yutaka ISHII  

     
    PAPER-Active Matrix Displays

      Vol:
    E85-C No:11
      Page(s):
    1849-1853

    We report, in this paper, on a combined process of photo-oxidation and PECVD using TEOS and O2 gases to produce an SiO2 gate insulator for poly-Si TFTs. Light of 172 nm-wavelength from a Xe excimer lamp generates active oxygen radicals efficiently and selectively without producing ozone. These oxygen radicals efficiently oxidize silicon. In contrast to plasma oxidation, photo-oxidation offers the ability to produce gate oxides without ion bombardment. Oxide-silicon interfaces with interface trap densities of 2-3 1010 cm-2 eV-1 were obtained by photo-oxidation at 200-300. A stack structure was produced using 4.3-nm-thick photo-oxide topped with a 40-nm-thick PECVD oxide film deposited at 300. This stack structure without annealing exhibited excellent interface behavior and the same J-E characteristics as a 100-nm-thick PECVD film annealed at 600.

  • Effects of N2O Plasma Treatment for Low Temperature Polycrystalline Silicon TFTs

    Yoshiki EBIKO  Yasuyoshi MISHIMA  

     
    PAPER-Active Matrix Displays

      Vol:
    E85-C No:11
      Page(s):
    1838-1843

    We present the effects of N2O plasma treatment for hot carrier reliability and gate oxide stability in excimer-laser annealed poly-Si TFTs. N2O plasma treatment between SiO2 and poly-Si suppresses both the reduction in mobility caused by hot carrier stress and the Vth shift caused by gate bias stress. The results of XPS spectra and the energy distribution of the trap state density of stressed TFTs show that the introduction of Si-N bonds plays an important role in poly-Si TFT reliability.

  • Approximation Algorithm of Series Expansion for Digital System Implementation

    Ki-Yun KIM  Hyung-Jin CHOI  Ho KIM  

     
    LETTER-Digital Signal Processing

      Vol:
    E85-A No:11
      Page(s):
    2532-2537

    This letter presents a new approximation algorithm suitable for Taylor series expansion. The algorithm can effectively reduce the approximation error by using only a small number of terms in series expansion. The proposed algorithm can be more easily implemented and has better performance than the conventional Euler approximation algorithm. Also, the approximation performance of the proposed algorithm is compared with direct approaches, such as least-squares and Chebyshev approximation algorithm to show the relative advantages of the proposed algorithm. This letter also presents an application example of the proposed approximation algorithm in carrier recovery of OFDM (Orthogonal Frequency Division Multiplexing) modem.

  • The Use of CNN for 2D Two-Channel DC IIR Filter Bank Design

    Emir Tufan AKMAN  Koray KAYABOL  

     
    LETTER-Image

      Vol:
    E85-A No:11
      Page(s):
    2551-2556

    In this letter, our proposed approach exploits the use of original and simplest Cellular Neural Network (CNN) for 2D Doubly Complementary (DC) Infinite Impulse Response (IIR) filter banks design. The properties of feedback and feedforward templates are studied for this purpose. Through some examples it is shown how generalizations of these templates can be used for DC IIR filter banks design. We modify Lagrangian function which is used for optimizing a low-pass filter design considering the constraint for stability of CNN. The brief conclusions with design examples that illustrate the proposed method and an image enhancement and restoration applications of designed filter banks are presented.

11501-11520hit(16314hit)