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12121-12140hit(20498hit)

  • Frequency Selective Shielding Screen by the Use of Artificial Media

    Tohru IWAI  Kennichi HATAKEYAMA  

     
    PAPER-Others

      Vol:
    E88-B No:8
      Page(s):
    3294-3299

    We calculated the shielding characteristic of a three-dimensional array of strip conductors by using the electric field integral equation method and its expansion to an array structure. From reflection coefficients, the effective permittivity of the array is calculated. The effective permittivity becomes negative in the frequency range above resonance, in which the electromagnetic waves travel through the material in an evanescent mode and the transmission coefficient becomes very small.

  • Characteristic Analysis and Enhancement of Sensing Property for Eddy-Current Type Proximity Sensor

    Koichi KOIBUCHI  Koichiro SAWA  Takashi HONMA  Takumi HAYASHI  Kuniyoshi UEDA  Hiroshi SASAKI  

     
    PAPER-Sensing Devices

      Vol:
    E88-C No:8
      Page(s):
    1696-1703

    An eddy-current type proximity sensor is a non-contact type sensing device to detect the approach of a conductor by increase of equivalent AC resistance of excitation coil due to eddy current loss in the conductor. In this paper, electromagnetic characteristics of the actual proximity sensor are calculated by FEM and the validity of numerical analysis results are studied. Furthermore, two models that has modified magnetic circuit geometry based on the actual sensor are designed and calculated as numerical experiments. Calculated results are shown as enhanced sensing index or electromagnetic characteristics of the modified sensor. In conclusions, knowledge about the magnetic circuit geometry of the sensor is applied for the enhancement of sensing property.

  • Resource Management in Layer 1 Virtual Private Networks

    Tomonori TAKEDA  Takumi OHBA  Ichiro INOUE  Shigeo URUSHIDANI  

     
    PAPER-Network

      Vol:
    E88-B No:8
      Page(s):
    3343-3352

    This paper proposes resource management in Layer 1 Virtual Private Networks (VPNs). We have been proposing Layer 1 VPNs that provide layer 1 services to multiple customers over the single optical network with per VPN control and management capabilities. We have proposed two resource management models for Layer 1 VPNs, which constitute different class of services. One is the shared model, where resources are shared among VPNs. The other is the dedicated model, where resources are explicitly pre-assigned to each VPN. In this paper, after introducing an overview of Layer 1 VPNs, we evaluate several path computation algorithms for these two models focusing on the multi layer network scenario. In the shared model, there are several existing studies for non-VPN cases, but considerations for VPN cases are not investigated. This paper evaluates algorithms originally proposed for non-VPN cases for use in VPN cases. Simulation results show that the path computation algorithm that works as saving layer 1 resources achieves better resource sharing effect. In the dedicated model, the problem is identical to non-VPN cases. There is one conventional algorithm, but amount of available resources is not well considered. We propose a novel path computation algorithm. Simulation results show effectiveness of our proposed algorithm against the conventional algorithm. Furthermore, resource usage efficiency of two resource management models is compared. We analyze and propose applicability of resource management models.

  • Genetic Design Method for Near-Optimal Training Sequences in Wideband Spatial Multiplexing Systems

    Toshiaki KOIKE  Hidekazu MURATA  Susumu YOSHIDA  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E88-B No:8
      Page(s):
    3488-3492

    In spatial multiplexing systems using multiple antennas, the error-rate performance is heavily dependent on the residual channel estimation error. In this letter, we propose a design method that uses the genetic algorithms to optimize training sequences for accurate channel estimation.

  • Mechanical Condition Monitoring of Vacuum Circuit Breakers Using Artificial Neural Network

    Yongpeng MENG   Shenli JIA  Mingzhe RONG  

     
    PAPER-Contactors & Circuit Breakers

      Vol:
    E88-C No:8
      Page(s):
    1652-1658

    Using the Vibration signatures obtained during the operations as the original data, a mechanical condition monitoring method for vacuum circuit breaker is developed in this paper. The method combined the time-frequency analysis and the condition recognition based on artificial neural network. During preprocessing, the vibration signature was decomposed into individual frequency bands using the arithmetic of wavelet packets. The signal energy in the main frequency bands was used to form the condition feature vector, which was input to the artificial neural network for condition recognition. By introducing the parameter of approximation degree, a new recognition arithmetic based on Radial Basis Function was constructed. This approach could not only distinguish these conditions that belong to different known condition modes but also distinguish new condition modes.

  • A New Generation Method of Slowly Rotating-EM Fields for Radiated Immunity/Susceptibility Test

    Kimitoshi MURANO  Majid TAYARANI  Fengchao XIAO  Yoshio KAMI  

     
    PAPER-Measurements

      Vol:
    E88-B No:8
      Page(s):
    3133-3139

    A new generation method of rotating electromagnetic fields (rotating-EM fields) for radio frequency (RF) radiated immunity/susceptibility test and its basic characteristics are described. Two different double-side-band suppressed-carrier (DSB-SC) signals are required for generating the slowly rotating-EM field for the immunity/susceptibility test. These DSB-SC signals are generated by a DSB-SC-signal generator based on the new concept which consists of voltage-variable attenuators, bi-phase switches, a direct-digital synthesizer and a micro processor. Using the DSB-SC-signal generator, the DSB-SC signal of arbitrary RF frequency can be generated more easily than the conventional system. In this paper, the principle of the DSB-SC signal generator and the basic characteristics of the DSB-SC signals generated by the generator are clarified. The measured basic characteristics of the rotating-EM field generated using the new concept are shown and it is confirmed that the field can be applied for the RF immunity/susceptibility test. In addition, the susceptibility test of an equipment under test is made as an example, the validity of our proposed system is established.

  • SoC R&D Trend for Future Digital Life

    Ki Won LEE  

     
    INVITED PAPER

      Vol:
    E88-C No:8
      Page(s):
    1705-1710

    This paper depicts the future R&D direction and the importance of SoC (System-on-Chip) based on a forecast of the Consumer Electronics trend in the Digital Convergence Era. Real-life examples of Samsung Electronics in order to solidify the competitiveness of its set products are presented.

  • Analysis of Crosstalk between Finite-Length Multiconductor Transmission Lines on a PCB by Using Circuit-Concept Approach

    Sang Wook PARK  Jae Cheol JU  Dong Chul PARK  

     
    PAPER-Printed Circuit Boards

      Vol:
    E88-B No:8
      Page(s):
    3189-3194

    In this paper, crosstalk between multiconductor transmission lines of finite length in arbitrary directions on a printed circuit board is studied by using a circuit-concept approach. The circuit-concept approach of (2+1) finite-length lines is expanded for the crosstalk calculation of (n+1) lines where n>2.2n-port network expression is derived from the modified telegrapher equations. The effect of via currents flowing through the vertical short line sections at the line terminals is also investigated. Due to this expansion the derived equations for (n+1) lines are expected to be easily applied for crosstalk analysis of a variety of complex structures such as via fences and guard traces, etc.

  • Optimal Design of Complex Two-Channel IIR QMF Banks with Equiripple Response

    Ju-Hong LEE  Yuan-Hau YANG  

     
    PAPER-Digital Signal Processing

      Vol:
    E88-A No:8
      Page(s):
    2143-2153

    The optimal design of complex infinite impulse response (IIR) two-channel quadrature mirror filter (QMF) banks with equiripple frequency response is considered. The design problem is appropriately formulated to result in a simple optimization problem. Therefore, based on a variant of Karmarkar's algorithm, we can efficiently solve the optimization problem through a frequency sampling and iterative approximation method to find the complex coefficients for the IIR QMFs. The effectiveness of the proposed technique is to form an appropriate Chebyshev approximation of a desired response and then find its solution from a linear subspace in several iterations. Finally, simulation results are presented for illustration and comparison.

  • Proposal of Shift Insensitive Wavelet Decomposition for Stable Analysis

    Tadashi MATSUO  Yasuo YOSHIDA  Nobuyuki NAKAMORI  

     
    PAPER-Image

      Vol:
    E88-A No:8
      Page(s):
    2087-2099

    The conventional complete discrete wavelet transform (DWT) is shift-sensitive, so that the analysis often becomes unstable. In this paper, we define a measure of shift-sensitivity, based on which we propose a new DWT less sensitive than the complete DWT. The measure is derived from the normalized variation of the output waveform for a shifted signal. The measure indicates that a narrow-band high-pass filter is desirable for shift-insensitivity. Then we propose a new DWT which makes use of a complex filter with half bandwidth of a high-pass filter of an ordinary DWT. In two dimensions, the proposed DWT can decompose an image into either four or six directional components which include two separate diagonals, while the complete DWT decomposes the image into three directional components. We show the effectiveness of our method by evaluating the shift-sensitivity of our DWT and other DWTs. By our DWT a smooth continuing edge of an image can be detected, but by the complete DWT a discontinuous edge is produced.

  • 0.18-µm CMOS 10-Gb/s Current-Mode Serial Link Transmitters

    Fei YUAN  Jean JIANG  

     
    PAPER-Communications and Wireless Systems

      Vol:
    E88-D No:8
      Page(s):
    1863-1869

    This paper presents the design of new fully differential CMOS class A and class AB current-mode transmitters for multi-Gbps serial links. A high multiplexing speed is achieved by multiplexing at low-impedance nodes and inductive shunt peaking with active inductors. The fully complementary operation of the multiplexers and the fully differential configuration of the transmitters minimizes the effect of common-mode disturbances and that of EMI from channels to neighboring devices. Large output current swing is obtained by making use of differential current amplifiers and the differential rail-to-rail configuration. The constant current drawn from the supply voltage minimizes the noise injected into the substrate. The transmitters have been implemented in TSMC's 1.8 V 0.18 µm CMOS technology and analyzed using Spectre from Cadence Design Systems with BSIM3V device models. Simulation results confirm that the proposed transmitters are capable of transmitting data at 10 Gbps.

  • Irregular Low-Density Convolutional Codes

    Linhua MA  Jun LIU  Yilin CHANG  

     
    LETTER-Coding Theory

      Vol:
    E88-A No:8
      Page(s):
    2240-2243

    A method for constructing low-density convolutional (LDC) codes with the degree distribution optimized for block low-density parity-check (LDPC) codes is presented. If the degree distribution is irregular, the constructed LDC codes are also irregular. In this letter we give the encoding and decoding method for LDC codes, and study how to avoid the short cycles of LDC codes. Some simulation results are also presented.

  • An Effective Built-In Self-Test for Chargepump PLL

    Junseok HAN  Dongsup SONG  Hagbae KIM  YoungYong KIM  Sungho KANG  

     
    LETTER

      Vol:
    E88-C No:8
      Page(s):
    1731-1733

    In order to provide an efficient test method for PLL which is a mixed-signal circuit widely used in most of SoCs, a novel BIST method is developed. The new BIST uses the change of phase differences generated by selectively alternating the feedback frequency. It provides an efficient structural test, reduces an area overhead and improves the test accessibility.

  • Invasiveness of an Optical Magnetic Field Probe

    Satoru ARAKAWA  Eiji SUZUKI  Hiroyasu OTA  Ken Ichi ARAI  Risaburo SATO  

     
    PAPER-Measurements

      Vol:
    E88-B No:8
      Page(s):
    3170-3175

    Electromagnetic field probes inevitably disturb the original distribution of the field when they are positioned close to a device. This disturbance in turn affects measurement accuracy and device operation. We developed an optical magnetic field probe, comprising a loop antenna element and an electro-optic crystal, for highly accurate magnetic near-field measurement in the GHz frequency range. We analyzed the invasiveness of the optical magnetic field probe quantitatively both experimentally and using finite difference time domain simulation. We found that eliminating the metal cable reduced the disturbance of the surrounding field that was to be measured. In addition, we investigated the magnetic field detection characteristics of the probe and its influence on the operation of a microstrip line. The optical magnetic field probe was less invasive and provided more accurate measurement.

  • Characteristics of Balance-Unbalance Conversion Factor and Radiated Emission for Differential Type Microstrip Lines with Partial Unbalance

    Ken FUJIYOSHI  Masatake SHIGENAGA  Chiharu MIYAZAKI  Masamitsu TOKUDA  

     
    PAPER-Printed Circuit Boards

      Vol:
    E88-B No:8
      Page(s):
    3200-3206

    In this paper, a balance-unbalance conversion factor (TCTL: Transverse Conversion Transfer Loss, TCL: Transverse Conversion Loss) and a radiated emission for differential type microstrip lines with a partial unbalance on a PCB (Printed Circuit Board) are investigated. As the result, after inserting an unbalance element, it can be seen that a radiated emission increased according to the deterioration of TCL. The calculated results of the TCTL and TCL by using 4-terminal pair network chain matrix agreed with the measured results very well. In order to calculate radiated emission from the differential type microstrip lines, a common mode current on differential type microstrip lines with a partial unbalance was calculated by using 4-terminal pair network chain matrix. The calculated results of the radiated emission also agreed with the measured results.

  • A Compact Design of W-Band High-Pass Waveguide Filter Using Genetic Algorithms and Full-Wave Finite Element Analysis

    An-Shyi LIU  Ruey-Beei WU  Yi-Cheng LIN  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E88-C No:8
      Page(s):
    1764-1771

    This paper proposes an efficient two-phase optimization approach for a compact W-band double-plane stepped rectangular waveguide filter design, which combines genetic algorithms (GAs) with the simplified transmission-line model and full-wave analysis. Being more efficient and robust than the gradient-based method, the approach can lead to a compact waveguide filter design. Numerical results show that the resultant waveguide filter design with 4 sections (total length 19.6 mm) is sufficient to meet the design goal and provides comparable performance to that with 8 sections (total length 35.6 mm) by the Chebyshev synthesis approach. Based on the present approach, nineteen compact high-pass waveguide filters have been implemented and measured at the W-band with satisfactory performance.

  • Timing-Driven Placement Based on Path Topology Analysis

    Feng CHENG  Junfa MAO  Xiaochun LI  

     
    LETTER-VLSI Design Technology and CAD

      Vol:
    E88-A No:8
      Page(s):
    2227-2230

    A timing-driven placement algorithm based on path topology analysis is presented. The optimization for path delay is transformed into cell location optimization. The algorithm pays much attention on path topologies and applies an effective force directed method to find cell target locations. Total wire length optimization is combined with the timing-driven placement algorithm. MCNC (Microelectronics Centre of North-Carolina) standard cell benchmarks are experimented and results show that our timing-driven placement algorithm can make the longest path delay improve up to 13% compared with wirelength driven placement.

  • Cathode and Anode Bright-Spot Behaviors of Breaking Arc between Electrical Contacts with Low Separating Speed

    Takayoshi ENDO  Junya SEKIKAWA  Takayoshi KUBONO  

     
    PAPER-Arc Discharge & Related Phenomena

      Vol:
    E88-C No:8
      Page(s):
    1596-1602

    In each contact material (Ag, Cu, Ni, and Fe), the breaking arcs occurring between an electrical contact pair in a resistive circuit of DC42 V/10.5 A were observed with a high-speed camera (1000 frames/s). Arc voltage and arc current were also measured simultaneously. By analyzing cathode and anode bright spots in the photographs, the positions of cathode and anode bright spots on contact surfaces were plotted on the graph. As a result, cathode and anode bright spots were found to express the characteristic motion in each material. Moreover, by comparing those results with the photograph of contact surface after all operations.

  • Human Body Impedance for Contact Current Measurement in Japan

    Yoshitsugu KAMIMURA  Katsuo KOMORI  Masahiro SHOJI  Yoshifumi YAMADA  Soichi WATANABE  Yukio YAMANAKA  

     
    PAPER-Biological Effects

      Vol:
    E88-B No:8
      Page(s):
    3263-3268

    The radio-frequency protection guideline of Japan recommend the limits of contact current for contact hazard due to an ungrounded metallic object under an electromagnetic field in the frequency range from 10 kHz to 15 MHz. To arrange the standard measurement methods of contact current in Japan, the contact body impedance for the Japanese in the frequency range from 75 kHz to 15 MHz is obtained, and the simplified equivalent circuit is determined using nonlinear least squares method. In addition, the human body impedance is obtained from numerical simulation using the impedance method and voxel human model, and compared it with measured one.

  • Influence of Phantom Shell on SAR Measurement in 3-6 GHz Frequency Range

    Teruo ONISHI  Shinji UEBAYASHI  

     
    PAPER-Biological Effects

      Vol:
    E88-B No:8
      Page(s):
    3257-3262

    This paper presents the results of an investigation on the effect of a thin low-dielectric material (phantom shell) on measuring the Specific Absorption Rate (SAR) in the frequency range of 3 to 6 GHz. The International Electrotechnical Commission (IEC) has started to develop a SAR measurement procedure in order to cover such frequencies. In the procedure, the SAR is measured in a liquid phantom, which is a shell filled with tissue-equivalent liquid. Although the shell is thin and has low-dielectric properties, the influence of the phantom shell is thought to increase at higher frequencies. Therefore, an investigation using the transmission line model and the Finite-Difference Time-Domain (FD-TD) method was conducted. To verify the FD-TD results, measurements were also carried out. The calculation results using the FD-TD method agree well with the measurement results. If the frequency is higher, the SAR is affected by the shell even though the shell is thinner and has much lower dielectric properties than those of the tissue-equivalent liquid. Specifically, the SAR with the shell is approximately 1.3 times higher than without the shell at 5.2 GHz for the maximum case. The deviations in the loss and the thickness for the shell do not affect the SAR more than the relative permittivity.

12121-12140hit(20498hit)