• 제목/요약/키워드: coded

검색결과 2,005건 처리시간 0.025초

Block Constrained Trellis Coded Vector Quantization of LSF Parameters for Wideband Speech Codecs

  • Park, Jung-Eun;Kang, Sang-Won
    • ETRI Journal
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    • 제30권5호
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    • pp.738-740
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    • 2008
  • In this paper, block constrained trellis coded vector quantization (BC-TCVQ) is presented for quantizing the line spectrum frequency parameters of the wideband speech codec. Both a predictive structure and a safety-net concept are combined into BC-TCVQ to develop the predictive BC-TCVQ. The performance of this quantization is compared with that of the linear predictive coding vector quantizer used in the AMRWB codec, demonstrating reductions in spectral distortion.

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페이딩 환경에 강한 트렐리스 부호화 방식의 성능분석 (Performance Analysis of a Robust Trellis Coded Modulation for a Correlated Fading Channel)

  • 임수환;황병대;오성근
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.117-120
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    • 2001
  • In this paper, we propose a robust trellis coded modulation for a correlated Rayleigh fading channel. This method use only one transmit antenna, which can achieve superior performance compared to Space-Time Trellis Coded Modulation (STTC) over a wide channel correlation range among transmit antennas. The code is designed to have the largest Euclidean distance between faded signals at the receiver. Computer simulations are performed to evaluate the frame error rate (FER) performance and to compare the proposed code with the conventional one.

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무선 통신 환경에서 OFDM 시스템을 위한 트렐리스 부호화 방식의 성능분석 (A performance analysis of Trellis Coded Modulation for OFDM systems in the Wireless Communications Environments)

  • 황병대;임수환;오성근
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.121-124
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    • 2001
  • In this paper, we propose a robust trellis coded OFDM(orthogonal frequency division multiplexing) system for wireless communications over frequency selective fading channels. Computer simulations show that the proposed system achieves the better frame error rate(FER) performance as compared with the conventional Space time coded OFDM system in the correlated channel with multiple transmitter antennas.

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Bandwidth-Adaptive Video Transmission Method for Heterogeneous Network Environment

  • Sakazawa, S.;Takishima, Y.;Wada, M.;Amano, K.
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1997년도 Proceedings International Workshop on New Video Media Technology
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    • pp.49-54
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    • 1997
  • For the purpose of a flexible coded video transmission over a heterogeneous network, we propose a new packetization method for coded video data. The proposed method achieves small degradation of coded picture quality in case of packet discard at the network node and does not require heavy processing load for bitrate control operation. Computer simulation results show that the bitrate reduction from 384 kb/s to 192 kb/s does not cause severe degradation in picture quality.

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트렐리스 부호화된 8PSK/CPSC를 위한 RSSE 방식 (Reduced-state sequence estimation for trellis-coded 8PSK/cyclic prefixed single carrier)

  • 고상보;강훈철;좌정우
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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    • pp.20-23
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    • 2003
  • A reduced-state sequence estimation(RSSE) for trellis-coded (TC) 8PSK/cyclic prefixed single carrier(CPSC) with minimum mean-square error-liner equalization(MMSE-LE) on frequency-selective Rayleigh fading channels is proposed. The Viterbi algorithm (VA) is used to search for the best path through the reduced-state trellis combined equalization and TCM decoding. The symbol error probability of the proposed scheme is confirmed by computer simulation.

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Novel Trellis-Coded Spatial Modulation over Generalized Rician Fading Channels

  • Zhang, Peng;Yuan, Dongfeng;Zhang, Haixia
    • ETRI Journal
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    • 제34권6호
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    • pp.900-910
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    • 2012
  • In this paper, a novel trellis-coded spatial modulation (TCSM) design method is presented and analyzed. Inspired by the key idea of trellis-coded modulation (TCM), the detailed analysis is firstly provided on the unequal error protection performance of spatial modulation constellation. Subsequently, the Ungerboeck set partitioning rule is proposed and applied to develop a general method to design the novel TCSM schemes. Different from the conventional TCSM approaches, the novel one based on the Ungerboeck set partitioning rule has similar properties as the classic TCM, which has simple but effective code design criteria. Moreover, the novel designed schemes are robust and adaptive to the generalized Rician fading channels, which outperform the traditional TCSM ones. For examples, the novel 4-, 8-, and 16-state TCSM schemes are constructed by employing different transmit antennas and different modulation schemes in different channel conditions. Simulation results clearly demonstrate the advantages of the novel TCSM schemes over the conventional ones.

Real Coded Biogeography-Based Optimization for Environmental Constrained Dynamic Optimal Power Flow

  • Kumar, A. Ramesh;Premalatha, L.
    • Journal of Electrical Engineering and Technology
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    • 제10권1호
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    • pp.56-63
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    • 2015
  • The optimization is an important role in wide geographical distribution of electrical power market, finding the optimum solution for the operation and design of power systems has become a necessity with the increasing cost of raw materials, depleting energy resources and the ever growing demand for electrical energy. In this paper, the real coded biogeography based optimization is proposed to minimize the operating cost with optimal setting of equality and inequality constraints of thermal power system. The proposed technique aims to improve the real coded searing ability, unravel the prematurity of solution and enhance the population assortment of the biogeography based optimization algorithm by using adaptive Gaussian mutation. This algorithm is demonstrated on the standard IEEE-30 bus system and the comparative results are made with existing population based methods.

RCGA를 이용한 PID 제어기의 모델기반 동조규칙 (Model-based Tuning Rules of the PID Controller Using Real-coded Genetic Algorithms)

  • 김도응;진강규
    • 제어로봇시스템학회논문지
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    • 제8권12호
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    • pp.1056-1060
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    • 2002
  • Model-based tuning rules of the PID controller are proposed incorporating with real-coded genetic algorithms. The optimal parameter sets of the PID controller for step set-point tracking are obtained based on the first-order time delay model and a real-coded genetic algorithm as an optimization tool. As for assessing the performance of the controllers, performance indices(ISE, IAE and ITAE) are adopted. Then tuning rules are derived using the tuned parameter sets, potential rule models and another real-coded genetic algorithm A set of simulation works is carried out to verify the effectiveness of the proposed rules.

원시 이원 BCH 부호를 사용한 Algebraic-Coded Cryptosystem (Algebraic-Coded Cryptosystem Using Primitive Binary BCH Codes)

  • 조용건;남길현
    • 한국국방경영분석학회지
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    • 제15권2호
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    • pp.94-104
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    • 1989
  • The concept of Algebraic-Coded Cryptosystem has been proposed recently but its application has not been developed yet. The primary object of this paper is to implement the Private-Key Algebraic-Coded Cryptosystem by using the primitive binary BCH codes. In the analysis of the cryptosystein, we find out the fact that there may exist other key pairs $S_i\;and\;P_i$ satisfying $G^*=S_{i},G_{s},P_{i}$ where $SG_{s}P$ is the original cryptosystem made by use of the systematic code generation matrix $G_{s}$.

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Coefficient Estimation of IIR Digital Filters Using a Real-Coded Genetic Algorithm

  • Lee, Yun-Hyung;So, Myung-Ok;Jin, Gang-Gyoo;Rhyu, Keel-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권7호
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    • pp.863-871
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    • 2007
  • This paper proposes a methodology to estimate the system coefficients for the infinite impulse response(IIR) digital filters using real code GA. In the traditional real coded GA, it adapts the general genetic operations, whereas in this paper the proposed real coded GA applies improved genetic operations in order to search the optimal solution in given problems. Each of unknown IIR digital coefficients collected as forms of a chromosome. Two illustrative examples including the band pass and band stop IIR digital filters are demonstrated to verify the proposed method.