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[Keyword] dual(419hit)

141-160hit(419hit)

  • Broadside Coupling High-Temperature Superconducting Dual-Band Bandpass Filter

    Yuta TAKAGI  Kei SATOH  Daisuke KOIZUMI  Shoichi NARAHASHI  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E96-C No:8
      Page(s):
    1033-1040

    This paper proposes a novel high-temperature superconducting dual-band bandpass filter (HTS-DBPF), that employs a broadside coupling structure, in which quarter-wavelength resonators are formed on opposite sides of each substrate. This structure provides a dual-band operation of the BPF and flexibility, in the sense of having a wide range in selecting two center passband frequencies of the HTS-DBPF. This paper employs the ratio of the lower and higher center passband frequencies, α, as a criterion for evaluating the flexibility. The obtained α ranges are from 1 to 4.7, which are the widest for DBPFs for mobile communications applications, to the best knowledge of the authors. This paper presents a 2.4-/2.9-GHz band HTS-DBPF, as an experimental example, using a YBCO film deposited on an MgO substrate. The measured frequency responses of the HTS-DBPF agree with the electromagnetic simulated results. Measurement and simulation results confirm that the proposed filter architecture is effective in configuring a DBPF that can set each center passband frequency widely.

  • Concurrent Detection and Recognition of Individual Object Based on Colour and p-SIFT Features

    Jienan ZHANG  Shouyi YIN  Peng OUYANG  Leibo LIU  Shaojun WEI  

     
    PAPER

      Vol:
    E96-A No:6
      Page(s):
    1357-1365

    In this paper we propose a method to use features of an individual object to locate and recognize this object concurrently in a static image with Multi-feature fusion based on multiple objects sample library. This method is proposed based on the observation that lots of previous works focuses on category recognition and takes advantage of common characters of special category to detect the existence of it. However, these algorithms cease to be effective if we search existence of individual objects instead of categories in complex background. To solve this problem, we abandon the concept of category and propose an effective way to use directly features of an individual object as clues to detection and recognition. In our system, we import multi-feature fusion method based on colour histogram and prominent SIFT (p-SIFT) feature to improve detection and recognition accuracy rate. p-SIFT feature is an improved SIFT feature acquired by further feature extraction of correlation information based on Feature Matrix aiming at low computation complexity with good matching rate that is proposed by ourselves. In process of detecting object, we abandon conventional methods and instead take full use of multi-feature to start with a simple but effective way-using colour feature to reduce amounts of patches of interest (POI). Our method is evaluated on several publicly available datasets including Pascal VOC 2005 dataset, Objects101 and datasets provided by Achanta et al.

  • A Dual-Mode Deblocking Filter Design for HEVC and H.264/AVC

    Muchen LI  Jinjia ZHOU  Dajiang ZHOU  Xiao PENG  Satoshi GOTO  

     
    PAPER

      Vol:
    E96-A No:6
      Page(s):
    1366-1375

    As the successive video compression standard of H.264/AVC, High Efficiency Video Codec (HEVC) will play an important role in video coding area. In the deblocking filter part, HEVC inherits the basic property of H.264/AVC and gives some new features. Based on this variation, this paper introduces a novel dual-mode deblocking filter architecture which could support both of the HEVC and H.264/AVC standards. For HEVC standard, the proposed symmetric unified-cross unit (SUCU) based filtering scheme greatly reduces the design complexity. As a result, processing a 1616 block needs 24 clock cycles. For H.264/AVC standard, it takes 48 clock cycles for a 1616 macro-block (MB). In synthesis result, the proposed architecture occupies 41.6k equivalent gate count at frequency of 200 MHz in SMIC 65 nm library, which could satisfy the throughput requirement of super hi-vision (SHV) on 60 fps. With filter reusing scheme, the universal design for the two standards saves 30% gate counts than the dedicated ones in filter part. In addition, the total power consumption could be reduced by 57.2% with skipping mode when the edges need not be filtered.

  • Channel Capacity Improvement in Near-Field MIMO System Using Metal Wires

    Dalin ZHANG  Toshikazu HORI  Mitoshi FUJIMOTO  

     
    PAPER-Antennas and Propagation

      Vol:
    E96-B No:5
      Page(s):
    1141-1148

    This paper clarifies the effects of metal wires placed around a Multiple-Input-Multiple-Output (MIMO) array with the goal of improving the channel capacity in near-field MIMO systems. Tests are performed on dual-dipole arrays with metal wires placed parallel to the dipoles. If the antenna elements have an appropriate half-power beamwidth (HPBW), there is a clear improvement in the channel capacity of the dual-dipole array. The metal wires are used to increase the multipath richness and the locations of the wires significantly impact the channel capacity. A significant increase in the channel capacity is observed even if only one metal wire is placed in the proper location. We verified the generality of applying a metal wire to improve the channel capacity and that the improvement in the channel capacity is approximately proportional to the number of metal wires.

  • All-Zero Block-Based Optimization for Quadtree-Structured Prediction and Residual Encoding in High Efficiency Video Coding

    Guifen TIAN  Xin JIN  Satoshi GOTO  

     
    PAPER-Digital Signal Processing

      Vol:
    E96-A No:4
      Page(s):
    769-779

    High Efficiency Video Coding (HEVC) outperforms H.264 High Profile with bitrate saving of about 43%, mostly because block sizes for hybrid prediction and residual encoding are recursively chosen using a quadtree structure. Nevertheless, the exhaustive quadtree-based partition is not always necessary. This paper takes advantage of all-zero residual blocks at every quadtree depth to accelerate the prediction and residual encoding processes. First, we derive a near-sufficient condition to detect variable-sized all-zero blocks (AZBs). For these blocks, discrete cosine transform (DCT) and quantization can be skipped. Next, using the derived condition, we propose an early termination technique to reduce the complexity for motion estimation (ME). More significantly, we present a two-dimensional pruning technique based on AZBs to constrain prediction units (PU) that contribute negligibly to rate-distortion (RD) performance. Experiments on a wide range of videos with resolution ranging from 416240 to 4k2k, show that the proposed scheme can reduce computational complexity for the HEVC encoder by up to 70.46% (50.34% on average), with slight loss in terms of the peak signal-to-noise ratio (PSNR) and bitrate. The proposal also outperforms other state-of-the-art methods by achieving greater complexity reduction and improved bitrate performance.

  • Content Adaptive Hierarchical Decision of Variable Coding Block Sizes in High Efficiency Video Coding for High Resolution Videos

    Guifen TIAN  Xin JIN  Satoshi GOTO  

     
    PAPER-Digital Signal Processing

      Vol:
    E96-A No:4
      Page(s):
    780-789

    The quadtree-based variable block sized prediction makes the biggest contribution for dramatically improved coding efficiency in the new video coding standard named HEVC. However, this technique takes about 75–80% computational complexity of an HEVC encoder. This paper brings forward an adaptive scheme that exploits temporal, spatial and transform-domain features to speed up the original quadtree-based prediction, targeting at high resolution videos. Before encoding starts, analysis on utilization ratio of each coding depth is performed to skip rarely adopted coding depths at frame level. Then, texture complexity (TC) measurement is applied to filter out none-contributable coding blocks for each largest coding unit (LCU). In this step, a dynamic threshold setting approach is proposed to make filtering adaptable to videos and coding parameters. Thirdly, during encoding process, sum of absolute quantized residual coefficient (SAQC) is used as criterion to prune useless coding blocks for both LCUs and 3232 blocks. By using proposed scheme, motion estimation is performed for prediction blocks within a narrowed range. Experiments show that proposed scheme outperforms existing works and speeds up original HEVC by a factor of up to 61.89% and by an average of 33.65% for 4kx2k video sequences. Meanwhile, the peak signal-to-noise ratio (PSNR) degradation and bit increment are trivial.

  • Development and Evaluation of a Wide Range Impulse Current Generator for Surge Arrester Testing

    Kuo-Hsiung TSENG  Ching-Lin HUANG  Pei-Yu CHENG  Zih-Ciao WEI  

     
    PAPER-Measurement Technology

      Vol:
    E96-A No:3
      Page(s):
    713-720

    This paper is focused on discussing a low-voltage system for lightning, and in particular the testing equipment of surge arresters. Only by demonstrating the performance and applicability of arresters can we seek the most feasible and economic low-voltage solutions. After performing repeated experiments with the same testing samples, using different testing equipment, we compare the different test results in order to select the most suitable and applicable testing equipment. In addition, the basis of a surge current parameter design theory is confirmed and verified through the test results using a simple and compact Impulse Current Generator to test a wide range of samples. By performing the actual analyzes and experiments, we can understand deeply how R, L, and C affect surge current, current wave, and current wave time. The ideal testing equipment standards have been set as follows: (1) Test Voltage up to 20 kV; (2) Expand current range from 1.5 kA to 46.5 kA, with resolution 1.5 kA; and (3) Simple operational procedures.

  • Low-Complexity Soft-ML Detection Algorithm for Modified-DCM in WiMedia UWB Systems

    Kilhwan KIM  Jangyong PARK  Jihun KOO  Yongsuk KIM  Jaeseok KIM  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E96-B No:3
      Page(s):
    910-913

    This letter proposes a low-complexity soft-detection algorithm for modified dual-carrier modulation (MDCM) in WiMedia ultra-wideband (UWB) systems. In order to reduce the complexity of soft-output maximum-likelihood detection (soft-MLD), which gives the optimal performance for MDCM symbols, the proposed algorithm utilizes the following three methods: real/imaginary separation, multiplierless distance calculation, and candidate set reduction. Through these methods, the proposed algorithm reduces the complexity of soft-MLD by 97%, while preventing the deterioration of its optimality. The performance of the proposed algorithm is demonstrated by simulations of 640–1024 Mbps transmission modes of the latest Release 1.5 standard of the WiMedia UWB.

  • Dual-Core Framework: Eliminating the Bottleneck Effect of Scalar Kernels on SIMD Architectures

    Yaohua WANG  Shuming CHEN  Hu CHEN  Jianghua WAN  Kai ZHANG  Sheng LIU  

     
    LETTER-Computer System

      Vol:
    E96-D No:2
      Page(s):
    365-369

    The efficiency of ubiquitous SIMD (Single Instruction Multiple Data) media processors is seriously limited by the bottleneck effect of the scalar kernels in media applications. To solve this problem, a dual-core framework, composed of a micro control unit and an instruction buffer, is proposed. This framework can dynamically decouple the scalar and vector pipelines of the original single-core SIMD architecture into two free-running cores. Thus, the bottleneck effect can be eliminated by effectively exploiting the parallelism between scalar and vector kernels. The dual-core framework achieves the best attributes of both single-core and dual-core SIMD architectures. Experimental results exhibit an average performance improvement of 33%, at an area overhead of 4.26%. What's more, with the increase of the SIMD width, higher performance gain and lower cost can be expected.

  • A 120 GHz/140 GHz Dual-Channel OOK Receiver Using 65 nm CMOS Technology

    Ryuichi FUJIMOTO  Mizuki MOTOYOSHI  Kyoya TAKANO  Minoru FUJISHIMA  

     
    PAPER

      Vol:
    E96-A No:2
      Page(s):
    486-493

    The design and measured results of a 120 GHz/140 GHz dual-channel OOK (ON-OFF Keying) receiver are presented in this paper. Because a signal with very wide frequency width is difficult to process in a single-channel receiver, a dual-channel configuration with channel selection is adopted in the proposed receiver. The proposed receiver is fabricated using 65 nm CMOS technology. The measured data rate of 3.0 and 3.6 Gbps, minimum sensitivity of -25.6 and -27.1 dBm, communication distance of 0.30 and 0.38 m are achieved in the 120- and 140-GHz receiver, respectively. The correct channel selection is achieved in the 120-GHz receiver. These results indicate the possibility of the CMOS multiband receiver operating at over 100 GHz for low-power high-speed proximity wireless communication systems.

  • Design of a Dual-Band Dual-Polarization Array Antenna with Improved Bandwidth for AMRFC Radar Application

    Youngki LEE  Deukhyeon GA  Daesung PARK  Seokgon LEE  Jaehoon CHOI  

     
    PAPER-Antennas and Propagation

      Vol:
    E96-B No:1
      Page(s):
    182-189

    A dual-band dual-polarization array antenna with improved bandwidth for an advanced multi-function radio function concept (AMRFC) radar application is proposed. To improve the S-band impedance bandwidth, the proposed antenna uses modified coupling feed patch. The measured bandwidth of the prototype array is 19.8% and 25.7% for the S- and X-band, respectively. The isolation between the two orthogonal polarizations is higher than 15 dB and cross-polarization level is less than -17 dB for both S- and X-bands.

  • Fast Bit-Parallel Polynomial Basis Multiplier for GF(2m) Defined by Pentanomials Using Weakly Dual Basis

    Sun-Mi PARK  Ku-Young CHANG  Dowon HONG  Changho SEO  

     
    PAPER-Algorithms and Data Structures

      Vol:
    E96-A No:1
      Page(s):
    322-331

    In this paper, we derive a fast polynomial basis multiplier for GF(2m) defined by pentanomials xm+xk3+xk2+xk1+1 with 1 ≤ k1 < k2 < k3 ≤ m/2 using the presented method by Park and Chang. The proposed multiplier has the time delay TA+(2+⌈log2(m-1)⌉) TX or TA+(3+⌈log2(m-1)⌉) TX which is the lowest one compared with known multipliers for pentanomials except for special types, where TA and TX denote the delays of one AND gate and one XOR gate, respectively. On the other hand, its space complexity is very slightly greater than the best known results.

  • L-Band SiGe HBT Frequency-Tunable Dual-Bandpass or Dual-Bandstop Differential Amplifiers Using Varactor-Loaded Series and Parallel LC Resonators

    Kazuyoshi SAKAMOTO  Yasushi ITOH  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E95-C No:12
      Page(s):
    1839-1845

    L-band SiGe HBT frequency-tunable differential amplifiers with dual-bandpass or dual-bandstop responses have been developed for the next generation adaptive and/or reconfigurable wireless radios. Varactor-loaded dual-band resonators comprised of series and parallel LC circuits are employed in the output circuit of differential amplifiers for realizing dual-bandpass responses as well as the series feedback circuit for dual-bandstop responses. The varactor-loaded series and parallel LC resonator can provide a wider frequency separation between dual-band frequencies than the stacked LC resonator. With the use of the varactor-loaded dual-band resonator in the design of the low-noise SiGe HBT differential amplifier with dual-bandpass responses, the lower-band frequency can be varied from 0.58 to 0.77 GHz with a fixed upper-band frequency of 1.54 GHz. Meanwhile, the upper-band frequency can be varied from 1.1 to 1.5 GHz for a fixed lower-band frequency of 0.57 GHz. The dual-band gain was 6.4 to 13.3 dB over the whole frequency band. In addition, with the use of the varactor-loaded dual-band resonator in the design of the low-noise differential amplifier with dual-bandstop responses, the lower bandstop frequency can be varied from 0.38 to 0.68 GHz with an upper bandstop frequency from 1.05 to 1.12 GHz. Meanwhile, the upper bandstop frequency can be varied from 0.69 to 1.02 GHz for a lower bandstop frequency of 0.38 GHz. The maximal dual-band rejection of gain was 14.4 dB. The varactor-loaded dual-band resonator presented in this paper is expected to greatly contribute to realizing the next generation adaptive and/or reconfigurable wireless transceivers.

  • A Fractional-N PLL with Dual-Mode Detector and Counter

    Fitzgerald Sungkyung PARK  Nikolaus KLEMMER  

     
    BRIEF PAPER-Integrated Electronics

      Vol:
    E95-C No:12
      Page(s):
    1887-1890

    A fractional-N phase-locked loop (PLL) is designed for the DigRF interface. The digital part of the PLL mainly consists of a dual-mode phase frequency detector (PFD), a digital counter, and a digital delta-sigma modulator (DSM). The PFD can operate on either 52 MHz or 26 MHz reference frequencies, depending on its use of only the rising edge or both the rising and the falling edges of the reference clock. The interface between the counter and the DSM is designed to give enough timing margin in terms of the signal round-trip delay. The circuitry is implemented using a 90-nm CMOS process technology with a 1.2-V supply, draining 1 mA.

  • Novel Voltage Choice and Min-Cut Based Assignment for Dual-VDD System

    Haiqi WANG  Sheqin DONG  Tao LIN  Song CHEN  Satoshi GOTO  

     
    PAPER-Physical Level Design

      Vol:
    E95-A No:12
      Page(s):
    2208-2219

    Dual-vdd has been proposed to optimize the power of circuits without violating the performance. In this paper, different from traditional methods which focus on making full use of slacks of non-critical gates, an efficient min-cut based voltage assignment algorithm concentrating on critical gates is proposed. And then this algorithm is integrated into a searching engine to auto-select rational voltages for dual-vdd system. Experimental results show that our search engine can always achieve good pair of dual-vdd, and our min-cut based algorithm outperformed previous works for voltage assignment both on power consumption and runtime.

  • High-Speed Low-Power Boosted Level Converters for Dual Supply Systems

    Sang-Keun HAN  KeeChan PARK  Young-Hyun JUN  Bai-Sun KONG  

     
    BRIEF PAPER-Electronic Circuits

      Vol:
    E95-C No:11
      Page(s):
    1824-1826

    This paper introduces novel high-speed and low-power boosted level converters for use in dual-supply systems. The proposed level converters adopt a voltage boosting at the gate of pull-down transistors to improve driving speed and reduce contention problem. Comparison results in a 0.13-µm CMOS process indicated that the proposed level converters provided up to 70% delay reduction with up to 57% power-delay product (PDP) reduction as compared to conventional level converters.

  • A Dual Band High Efficiency Class-F GaN Power Amplifier Using a Novel Harmonic-Rejection Load Network

    Yongchae JEONG  Girdhari CHAUDHARY  Jongsik LIM  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E95-C No:11
      Page(s):
    1783-1789

    A class-F high efficiency GaN power amplifier (PA) for dual band operation at 2.14 GHz and 2.35 GHz is proposed. A novel dual band harmonic-rejection load network, which controls the terminating impedances of the second and third harmonics, and contributes greatly to efficiency improvement of PA, is described. In addition, a matching network which guarantees the high efficiency and gain of PA for the desired dual bands is designed. The proposed load network has the harmonic rejection of more than 24 dB which is sufficient for rejecting harmonics, and an insertion loss of less than 0.11 dB. The dual band matching network for the maximum output power results in the measured highest output power for each operating frequency. The fabricated class-F GaN PA has 43 dBm-65.4% and 43 dBm-63.9% of output power - efficiency at the desired dual frequencies.

  • A Comprehensive Instrument for Measuring Individual Competency of IT Applications in an Enterprise IT Environment

    Chui Young YOON  

     
    PAPER-Artificial Intelligence, Data Mining

      Vol:
    E95-D No:11
      Page(s):
    2651-2657

    An instrument that can efficiently measure individual competency of IT applications (ICITA) is presented. It allows an organization to develop and manage the IT application capability of individuals working in an enterprise IT environment. The measurement items are generated from the definition and major components of individual competency of IT applications. The reliability and validity of the instrument construct are verified by factor and correlation analysis. A 15-item instrument is proposed to efficiently measure individual competency of IT applications and the instrument will contribute to the improved ICITA of human resources working in an enterprise IT environment.

  • Design of High-Performance Asynchronous Pipeline Using Synchronizing Logic Gates

    Zhengfan XIA  Shota ISHIHARA  Masanori HARIYAMA  Michitaka KAMEYAMA  

     
    PAPER-Integrated Electronics

      Vol:
    E95-C No:8
      Page(s):
    1434-1443

    This paper introduces a novel design method of an asynchronous pipeline based on dual-rail dynamic logic. The overhead of handshake control logic is greatly reduced by constructing a reliable critical datapath, which offers the pipeline high throughput as well as low power consumption. Synchronizing Logic Gates (SLGs), which have no data dependency problem, are used in the design to construct the reliable critical datapath. The design targets latch-free and extremely fine-grain or gate-level pipeline, where the depth of every pipeline stage is only one dual-rail dynamic logic. HSPICE simulation results, in a 65 nm design technology, indicate that the proposed design increases the throughput by 120% and decreases the power consumption by 54% compared with PS0, a classic dual-rail asynchronous pipeline implementation style, in 4-bit wide FIFOs. Moreover, this method is applied to design an array style multiplier. It shows that the proposed design reduces power by 37.9% compared to classic synchronous design when the workloads are 55%. A chip has been fabricated with a 44 multiplier function, which works well at 2.16G data-set/s (Post-layout simulation).

  • Hybrid Resource Allocation Scheme with Proportional Fairness in OFDMA-Based Cognitive Radio Systems

    Li LI  Changqing XU  Pingzhi FAN  Jian HE  

     
    LETTER-Communication Theory and Signals

      Vol:
    E95-A No:8
      Page(s):
    1430-1434

    In this paper, the resource allocation problem for proportional fairness in hybrid Cognitive Radio (CR) systems is studied. In OFDMA-based CR systems, traditional resource allocation algorithms can not guarantee proportional rates among CR users (CRU) in each OFDM symbol because the number of available subchannels might be smaller than that of CRUs in some OFDM symbols. To deal with this time-varying nature of available spectrum resource, a hybrid CR scheme in which CRUs are allowed to use subchannels in both spectrum holes and primary users (PU) bands is adopted and a resource allocation algorithm is proposed to guarantee proportional rates among CRUs with no undue interference to PUs.

141-160hit(419hit)