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[Keyword] ROM(701hit)

261-280hit(701hit)

  • Parallel Parity Checksum and Syndrome Generation for Digital Video and Audio Transmission over Cable Channel

    Eonpyo HONG  Eungu JUNG  Junhee HONG  Jaewon YIM  Dongsoo HAR  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E92-D No:7
      Page(s):
    1435-1441

    The ITU-T J.83 Annex B is a widely adopted standard in North America for digital video and audio transmission over coaxial cable. This paper proposes a new parallel processing architecture of the parity checksum generator and syndrome generator specified in the standard for packet synchronization and error detection. The proposed parallel processing architecture removes the performance bottleneck occurring in the conventional serial processing architecture, leading to significant decrease in processing time for generating a parity checksum in transmitter and a syndrome in receiver. Implementation results show that the proposed parallel processing architecture reduces the processing time by 92% for parity checksum generation and by 81% for syndrome generation over the conventional serial processing architecture.

  • Novel Electromagnetic Bandgap with Triangular Unit Cells for Ultra-Broadband Suppression of Simultaneous Switching Noise

    Jong Hwa KWON  Dong Uk SIM  Sang Il KWAK  Jong Gwan YOOK  

     
    LETTER-Electromagnetic Compatibility(EMC)

      Vol:
    E92-B No:6
      Page(s):
    2356-2358

    To build a stable power distribution network for high-speed digital systems, simultaneous switching noise (SSN) should be sufficiently suppressed in multi-layer PCBs and packages. In this paper, a novel hybrid uni-planar compact electromagnetic bandgap (UC-EBG) with two triangular-type unit cells designed on power/ground planes is proposed for the ultra-broadband suppression of SSN. The SSN suppression performance of the proposed structure is validated both numerically and experimentally. A -35 dB suppression bandwidth for SSN is achieved, starting at 800 MHz and extending to 15 GHz and beyond, thereby covering almost the entire noise band.

  • Prediction of EM Radiation from a PCB Driven by a Connected Feed Cable

    Yoshiki KAYANO  Hiroshi INOUE  

     
    PAPER

      Vol:
    E92-B No:6
      Page(s):
    1920-1928

    Printed circuit boards (PCBs) driven by a connected feed cable are considered to be one of the main sources of the electromagnetic interference (EMI) from electronic devices. In this paper, a method for predicting the electromagnetic (EM) radiation from a PCB driven by a connected feed cable at up to gigahertz frequencies is proposed and demonstrated. The predictive model is based on the transmission line theory and current- and voltage-driven CM generation mechanisms with consideration of antenna impedance. Frequency responses of differential-mode (DM) and common-mode (CM) currents and far-electric field were investigated experimentally and with finite-difference time-domain (FDTD) modeling. First, the dominant component in total EM radiation from the PCB was identified by using the Source-Path-Antenna model. Although CM can dominate the total radiation at lower frequencies, DM is the dominant component above 3 GHz. Second, the method for predicting CM component at lower frequencies is proposed. And its validity was discussed by comparing FDTD calculated and measured results. Specifically, the relationship between the CM current and the terminating resistor was focused as important consequence for the prediction. Good agreement between the measured and predicted results shows the validity of the predicted results. The proposed model can predict CM current with sufficient accuracy, and also identify the primary coupling-mechanism of CM generation. Then far-electric field was predicted by using the proposed method, and it was demonstrated that outline of the frequency response of the undesired EM radiation from the PCB driven by the connected feed cable can be predicted with engineering accuracy (within 6 dB) up to 18 GHz. Finally, as example of application of equivalent circuit model to EMC design, effect of the width of the ground plane was predicted and discussed. The equivalent circuit model provides enough flexibility for different geometrical parameters and increases our ability to provide insights and design guidelines.

  • The Effect of Position of a Connector Contact Failure on Electromagnetic Near-Field around a Coaxial Cable

    Yu-ichi HAYASHI  Hideaki SONE  

     
    PAPER

      Vol:
    E92-B No:6
      Page(s):
    1969-1973

    A transmission line created by cables adjoined by connectors is influenced by noise from connectors with contact failure, and such noise degrades communication quality. The authors used a model of a connector with increased contact resistance in a coaxial cable and measured the electromagnetic near-field around a cable while changing positions of the model. In this paper, the result shows that the radiated electromagnetic field has no relationship with the position along the cable of a connector with increased contact resistance, when the contact condition of connector, contact resistance value, measurement position, and length of a transmission line are constant.

  • Hodgkin-Huxley Model-Based Analysis of Electric-Field Effect on Nerve Cell Using Self-Organizing Map

    Masao MASUGI  Kazuo MURAKAWA  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E92-B No:6
      Page(s):
    2182-2192

    This paper describes an analysis of the effects of electric field on nerve cells by using the Hodgkin-Huxley model. When evaluating our model, which combines an additional ionic current source and generated membrane potential, we derive the peak-to-peak value, the accumulated square of variation, and Kolmogorov-Sinai (KS) entropy of the cell-membrane potential excited by 10, 100, 1 k, and 10 kHz-sinusoidal electric fields. In addition, to obtain a comprehensive view of the time-variation patterns of our model, we used a self-organizing map, which provides a way to map high-dimensional data onto a low-dimensional domain. Simulation results confirmed that lower-frequency electric fields tended to increase fluctuations of the cell-membrane potential, and the additional ionic current source was a more dominant factor for fluctuations of the cell-membrane potential. On the basis of our model, we visually confirmed that the obtained data could be projected onto the map in accordance with responses of cell-membrane potential excited by electric fields, resulting in a combined depiction of the effects of KS entropy and other parameters.

  • Slit-Mura Detection through Non-contact Optical Measurements of In-Line Spectrometer for TFT-LCDs

    Fu-Ming TZU  Jung-Hua CHOU  

     
    PAPER-Electronic Displays

      Vol:
    E92-C No:3
      Page(s):
    364-369

    Slit-Mura defect is a notorious yield flaw of color filters. In this study, an innovative non-contact in-line optical inspection method is developed to detect low contrast slit Mura through quantitative measurements by a spectrometer. Using the features of either thickness or chromaticity profiles across a slit Mura, a thickness difference from 21 nm to 41 nm of color filters can be differentiated accurately. Thus, the quality of color filters can be accessed in-line during the manufacturing process TFT-LCDs.

  • The ROM Design with Half Grouping Compression Method for Chip Area and Power Consumption Reduction

    Ki-Sang JUNG  Kang-Jik KIM  Young-Eun KIM  Jin-Gyun CHUNG  Ki-Hyun PYUN  Jong-Yeol LEE  Hang-Geun JEONG  Seong-Ik CHO  

     
    PAPER-Integrated Electronics

      Vol:
    E92-C No:3
      Page(s):
    352-355

    In memory design, the issue is smaller size and low power. Most power used in the ROM is consumed in line capacitance such as address lines, word lines, bit lines, and decoder. This paper presents ROM design of a novel HG (Half Grouping) compression method so as to reduce the parasitic capacitance of bit lines and the area of the row decoder for power consumption and chip area reduction. ROM design result of 512 point FFT block shows that the proposed method reduces 40.6% area, 42.12% power, and 37.82% transistor number respectively in comparison with the conventional method. The designed ROM with proposed method is implemented in a 0.35 µm CMOS process. It consumes 5.8 mW at 100 MHz with a single 3.3 V power supply.

  • Static and Dynamic Signal Processing Methods for Noise Cancellation in Sound and Electromagnetic Environment

    Hisako MASUIKE  Akira IKUTA  

     
    PAPER

      Vol:
    E92-A No:3
      Page(s):
    753-761

    The observed phenomena in actual sound and electromagnetic environment are inevitably contaminated by the background noise of arbitrary distribution type. Therefore, in order to evaluate sound and electromagnetic environment, it is necessary to establish some signal processing methods to remove the undesirable effects of the background noise. In this paper, we propose noise cancellation methods for estimating a specific signal with the existence of background noise of non-Gaussian distribution from two viewpoins of static and dynamic signal processing. By applying the well-known least mean squared method for the moment statistics with several orders, practical methods for estimating the specific signal are derived. The effectiveness of the proposed theoretical methods is experimentally confirmed by applying them to estimation problems in actual sound and magnetic field environment.

  • A Chromatic Adaptation Model for Mixed Adaptation Conditions

    Jin-Keun SEOK  Sung-Hak LEE  Kyu-Ik SOHNG  

     
    LETTER

      Vol:
    E92-A No:3
      Page(s):
    843-846

    When we watch television or computer monitor under a certain viewing condition, we partially adapt to the display and partially to the ambient light. As an illumination level and chromaticity change, the eye's subjective white point changes between the display's white point and the ambient light's white point. In this paper, we propose a model that could predict the white point under a mixed adaptation condition including display and illuminant. Finally we verify this model by experimental results.

  • Neural Network Compensation for Frequency Cross-Talk in Laser Interferometry

    Wooram LEE  Gunhaeng HEO  Kwanho YOU  

     
    LETTER-Measurement Technology

      Vol:
    E92-A No:2
      Page(s):
    681-684

    The heterodyne laser interferometer acts as an ultra-precise measurement apparatus in semiconductor manufacture. However the periodical nonlinearity property caused from frequency cross-talk is an obstacle to improve the high measurement accuracy in nanometer scale. In order to minimize the nonlinearity error of the heterodyne interferometer, we propose a frequency cross-talk compensation algorithm using an artificial intelligence method. The feedforward neural network trained by back-propagation compensates the nonlinearity error and regulates to minimize the difference with the reference signal. With some experimental results, the improved accuracy is proved through comparison with the position value from a capacitive displacement sensor.

  • All-Optical Demultiplexing from 160 to 40/80 Gb/s Using Mach-Zehnder Switches Based on Intersubband Transition of InGaAs/AlAsSb Coupled Double Quantum Wells Open Access

    Ryoichi AKIMOTO  Guangwei CONG  Masanori NAGASE  Teruo MOZUME  Hidemi TSUCHIDA  Toshifumi HASAMA  Hiroshi ISHIKAWA  

     
    INVITED PAPER

      Vol:
    E92-C No:2
      Page(s):
    187-193

    We demonstrated all-optical demultiplexing of 160-Gb/s signal to 40- and 80-Gb/s by a Mach-Zehnder Interferometric all-optical switch, where the picosecond cross-phase modulation (XPM) induced by intersubband excitation in InGaAs/AlAsSb coupled double quantum wells is utilized. A bi-directional pump configuration, i.e., two control pulses are injected from both sides of a waveguide chip simultaneously, increases a nonlinear phase shift twice in comparison with injection of single pump beam with forward- and backward direction. The bi-directional pump configuration is the effective way to avoid damaging waveguide facets in the case where high optical power of control pulse is necessary to be injected for optical gating at repetition rate of 40/80 GHz. Bit error rate (BER) measurements on 40-Gb/s demultiplexed signal show that the power penalty is decreased slightly for the bi-directional pump case in the BER range less than 10-6. The power penalty is 1.3 dB at BER of 10 - 9 for the bi-directional pump case, while it increases by 0.3-0.6 dB for single pump cases. A power penalty is influenced mainly by signal attenuation at "off" state due to the insufficient nonlinear phase shift, upper limit of which is constrained by the current low XPM efficiency of 0.1 rad/pJ and the damage threshold power of 100 mW in a waveguide facet.

  • Estimation of Reflection Coefficient and Surface Impedance from Absolute Values of the Near Field with Periodic Change

    Michinari SHIMODA  Masazumi MIYOSHI  Kazunori MATSUO  Yoshitada IYAMA  

     
    PAPER

      Vol:
    E92-C No:1
      Page(s):
    92-101

    An inverse scattering problem of estimating the reflection coefficient and the surface impedance from two sets of absolute values of the near field with periodic change is investigated. The problem is formulated in terms of a nonlinear simultaneous equations which is derived from the relation between the two sets of absolute values and the field defined by a finite summation of the modal functions by applying the Fourier analysis. The reflection coefficient is estimated by solving the equations by Newton's method through the successive algorithm with the increment of the number of truncation in the summation one after another. Numerical examples are given and the accuracy of the estimation is discussed.

  • In Situ Observation of Time Dependent Electrochemical Activity of Cytochrome c at Bare Indium-Tin-Oxide Electrodes by Cyclic Voltammetry and Slab Optical Waveguide Spectroscopy

    Yusuke AYATO  Akiko TAKATSU  Kenji KATO  Naoki MATSUDA  

     
    PAPER-Bioelectronics

      Vol:
    E91-C No:12
      Page(s):
    1899-1904

    In situ observation of electrochemical activity and time dependent characteristics of cytochrome c (cyt c) was carried out in 0.01 M phosphate buffered saline (PBS, pH 7.4) containing 20 µM cyt c solutions at bare indium-tin-oxide (ITO) electrodes by using a cyclic voltammetry (CV) and a slab optical waveguide (SOWG) spectroscopy. The bare ITO electrodes could retain the electrochemical activity of cyt c in the PBS solutions, indicating the great advantage of using ITO electrodes against other electrode materials, such as gold (Au). The CV curves and simultaneously observed the time-resolved SOWG absorption spectra in the consecutive cycles implied that the cyt c molecules could retain its own electrochemical function for a long time.

  • Frequency Shifted Optical SSB Modulation Scheme and Its Application to SCM Transmission

    Toshihito FUJIWARA  Koji KIKUSHIMA  

     
    LETTER-Fiber-Optic Transmission for Communications

      Vol:
    E91-B No:12
      Page(s):
    4003-4005

    We propose frequency shifted optical single sideband (OSSB), a novel OSSB modulation scheme. It uses a continuous wave to up-convert the source signal, and the signal and the continuous wave then undergo suppressed carrier OSSB modulation simultaneously. This scheme inherently has no unwanted sidebands, even if the suppressed carrier OSSB modulator is defective. Experiments of 12 GHz RF signal transmission confirm that it achieves 2.4 dB relaxation in chromatic dispersion power fading under the condition of 15 dB SSR.

  • Design of Measurement Apparatus for Electromagnetic Shielding Effectiveness Using Flanged Double Ridged Waveguide

    Jong Hwa KWON  Jae Ick CHOI  Jong Gwan YOOK  

     
    LETTER-Electromagnetic Compatibility(EMC)

      Vol:
    E91-B No:12
      Page(s):
    4071-4074

    In this paper, we design and manufacture a flanged double ridged waveguide with a tapered section as a sample holder for measuring the electromagnetic shielding effectiveness (SE) of planar material in broadband frequency ranges up to 10 GHz. The proposed technique overcomes the limitations of the conventional ASTM D4935 test method at high frequencies. The simulation results for the designed sample holders agree well with the fabricated ones in consideration of the design specification of S11 < -20 dB within the frequency range of 1-10 GHz. To verify the proposed measurement apparatus, the measured SE data of the commercial shielding materials from 1 to 10 GHz were indirectly compared with those obtained from the ASTM D4935 from 30 MHz to 1 GHz. We observed that the SE data obtained by using both experimental techniques agree with each other.

  • Electrochromic Thin Film of Water-Dispersible Prussian-Blue Nanoparticles

    Ayako OMURA  Hirofumi SHIOZAKI  Shigeo HARA  Tohru KAWAMOTO  Akihito GOTOH  Masahito KURIHARA  Masaomi SAKAMOTO  Hisashi TANAKA  

     
    LETTER-Materials & Devices

      Vol:
    E91-C No:12
      Page(s):
    1887-1888

    The insoluble Prussian-blue (PB) pigment becomes possible to disperse in aqueous solution by covering their surfaces with ferrocyanide anions. The thin film fabricated with these water-dispersible PB nanoparticles shows evident electrochromic color changes between +0.8 V to -0.4 V on an ITO substrate. The mass change of the thin film during an electrochemical reaction is measured by means of electrochemical quartz crystal microbalance (EQCM). According to the EQCM analysis, the filling rate of water-dispersible PB nanoparticles in the film is 37.7% as compared with an assumed perfect crystal PB film.

  • Ultra Wideband Electromagnetic Phantoms for Antennas and Propagation Studies

    Hironobu YAMAMOTO  Jian ZHOU  Takehiko KOBAYASHI  

     
    PAPER

      Vol:
    E91-A No:11
      Page(s):
    3173-3182

    Ultra wideband (UWB) technologies are expected to be used in ultra-high-speed wireless personal area networks (WPAN) and wireless body area networks (WBAN). UWB human electromagnetic phantoms are useful for performance evaluation of antennas mounted in the vicinity of a human body and channel assessment when a human body blocks a propagation path. Publications on UWB phantoms, however, have been limited so far. This paper describes the development of liquid UWB phantom material (aqueous solution of sucrose) and UWB arm and torso phantoms. The UWB phantoms are not intended to evaluate a specific absorption rate (SAR) in a human body, because UWB devices are supposed to transmit at very low power and thus should pose no human hazard.

  • An Illumination-Adaptive Colorimetric Measurement Using Color Image Sensor

    Sung-Hak LEE  Jong-Hyub LEE  Kyu-Ik SOHNG  

     
    LETTER

      Vol:
    E91-C No:10
      Page(s):
    1608-1610

    An image sensor for a use of colorimeter is characterized based on the CIE standard colorimetric observer. We use the method of least squares to derive a colorimetric characterization matrix between RGB output signals and CIE XYZ tristimulus values. This paper proposes an adaptive measuring method to obtain the chromaticity of colored scenes and illumination through a 33 camera transfer matrix under a certain illuminant. Camera RGB outputs, sensor status values, and photoelectric characteristic are used to obtain the chromaticity. Experimental results show that the proposed method is valid in the measuring performance.

  • Skin Color Segmentation Using Coarse-to-Fine Region on Normalized RGB Chromaticity Diagram for Face Detection

    Aryuanto SOETEDJO  Koichi YAMADA  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E91-D No:10
      Page(s):
    2493-2502

    This paper describes a new color segmentation based on a normalized RGB chromaticity diagram for face detection. Face skin is extracted from color images using a coarse skin region with fixed boundaries followed by a fine skin region with variable boundaries. Two newly developed histograms that have prominent peaks of skin color and non-skin colors are employed to adjust the boundaries of the skin region. The proposed approach does not need a skin color model, which depends on a specific camera parameter and is usually limited to a particular environment condition, and no sample images are required. The experimental results using color face images of various races under varying lighting conditions and complex backgrounds, obtained from four different resources on the Internet, show a high detection rate of 87%. The results of the detection rate and computation time are comparable to the well known real-time face detection method proposed by Viola-Jones [11],[12].

  • A Method for Recognizing Noisy Romanized Japanese Words in Learner English

    Ryo NAGATA  Jun-ichi KAKEGAWA  Hiromi SUGIMOTO  Yukiko YABUTA  

     
    PAPER-Educational Technology

      Vol:
    E91-D No:10
      Page(s):
    2458-2466

    This paper describes a method for recognizing romanized Japanese words in learner English. They become noise and problematic in a variety of systems and tools for language learning and teaching including text analysis, spell checking, and grammatical error detection because they are Japanese words and thus mostly unknown to such systems and tools. A problem one encounters when recognizing romanized Japanese words in learner English is that the spelling rules of romanized Japanese words are often violated. To address this problem, the described method uses a clustering algorithm reinforced by a small set of rules. Experiments show that it achieves an F-measure of 0.879 and outperforms other methods. They also show that it only requires the target text and an English word list of reasonable size.

261-280hit(701hit)