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Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time trellis Coding (STTC)

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International Journal of Communications, Network and System Sciences 2009年第6期2卷 469-479页

作者： Peh Keong TEH Seyed ZEKAVAT 不详

In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas.

关键词： Antenna Array Beam Pattern Sweeping Transmit Diversity Space-Time Block Codes and Space-Time trellis Coding

Improved Super-Orthogonal trellis-Coded Spatial Modulation Using STBC-CSM

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Journal of Computer and Communications 2018年第12期6卷 149-156页

作者： Ammar M. Abu-Hudrouss Electrical Engineering Department Islamic University of Gaza Gaza Palestine

trellis coded modulation (TCM) is a scheme that enhances the error performance without extra power not bandwidth. This paper presents a modified Super-Orthogonal trellis-Coded Spatial Modulation (SOTC-SM) based on a cyclic structure of the Space Time Coding. The developed code benefits from expanded codebook of the Space Time Block Coded Spatial Modulation (STBC-SM) to enhance the coding gain. The set-partitioning and the code design based on the expanded codebook was given for codes with rate of 2 and 3 bps and can be easily extended to higher rates. The Bit-Error Rate (BER) performance of the proposed scheme was evaluated via computer simulation. It was shown that the proposed scheme outperforms the SOTC-SM performance for the same number of transmit antennas.

关键词： Space Time Block Coding Spatial Modulation trellis Cyclic STBC-SM SOTC-SM Set Partitioning

A REDUCED-STATE trellis FOR FULL RESPONSE CPM

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Journal of Electronics(China) 1996年第4期13卷 380-383页

作者： Li Bin(institute of Communications Engineering Nanjing 210016)Cheng Shixin(Southeast University Nanjing 210018)

The error performance of contimuons phase modulation (CPM) with the optimal coherent detection depends on its minimum squared Euclidean distance (MSED). In this paper, a reduced-state trellis for full response CPM is presented under the condition that the MSED is not reduced. and therefore the complexity of the Viterbi decoding is roduced.

关键词： Continuous phase modulation Optimal coherent detection Reduced-state trellis Viterbi decoding

Construction of minimal trellises for quantum stabilizer codes

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Science China(Information Sciences) 2013年第1期56卷 208-218页

作者： XIAO FangYing CHEN HanWu School of Computer Science and Engineering Southeast University

The size of vertex set of quantum trellises affects the efficiency of decoding algorithms,which can be improved by reducing the number of *** on the standard check matrix of stabilizer codes,an algorithm to construct trellis-oriented generators for quantum stabilizer codes is *** using this algorithm,the trellises with minimal vertex set can be *** addition,an algorithm to construct trellises iteratively for quantum stabilizer codes is also *** algorithm proposed in this paper is more efficient and less complex than the one proposed by Olliver,and so is more suitable for the applications of larger scale and stricter timeliness.

关键词： quantum stabilizer code check matrix trellis Pauli matrix

Estimating Digital Inter-Symbol Interference Channel Blindly Based on the One-Step Branch Transition Rules in trellises

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The Journal of China Universities of Posts and Telecommunications 2000年第1期7卷 104-107页

作者： OUYANG Cong-xing, WANG Li-ning, YUE Guang-xin (Institute of Telecommunications Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, P.R. China) Institute of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

A novel discrete-time digital inter-symbol interference (ISI) channel blind estimation sub-optimal algorithm is proposed. This algorithm reduces the complexity of the optimal maximum likelihood sequence estimation (MLSE) considerably based on the one-step branch transition rules in trellises, and is suitable for the estimation of the channels with small lengths of ISI.

关键词： trellis digital transmission channel blind estimation Markov transition probability matrix

采用辅助网格的4D-8PSK-TCM维特比译码

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空间科学学报 2008年第6期28卷 578-583页

作者：黄远达熊蔚明孙辉先中国科学院空间科学与应用研究中心北京100190 中国科学院研究生院

由于地球探测卫星(EESS)的不断增加,空间数据传输的频带日趋拥挤.为此,空间频率协调组织(SFCG)建议采用高效率调制技术(调制效率不低于1.75bit/symbol)进行数据传输,以有效地利用空间的频率资源,从而避免由于拥挤导致的临近频带之间的... 详细信息

由于地球探测卫星(EESS)的不断增加,空间数据传输的频带日趋拥挤.为此,空间频率协调组织(SFCG)建议采用高效率调制技术(调制效率不低于1.75bit/symbol)进行数据传输,以有效地利用空间的频率资源,从而避免由于拥挤导致的临近频带之间的相互干扰.4D-8PSK-TCM是CCSDS(空间数据系统咨询委员会)针对SFCG关于EESS 8025～8400 MHz频带调制效率不低于1.75 bit/symbol的高效率调制要求而提出的高效率编码调制标准,在满足抗噪声性能要求的基础上,有效地提高了频带利用率.本文研究了调制效率为2.5比特/符号的4D-8PSK-TCM系统及其维特比译码算法,并在Matlab Simulink下进行了维特比译码算法的仿真.在算法实现中,针对路径度量的复杂性,采用了一种辅助网格的方法,使计算路径度量时只需要64次比较,相对于直接计算所需的2032次比较,极大降低了路径度量的运算复杂度.

关键词： TCM 维特比 Auxiliary trellis

Improved MPEG-4 High-Efficiency AAC With Variable-Length Soft-Decision Decoding of the Quantized Spectral Coefficients

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China Communications 2019年第10期16卷 65-82页

作者： Sai Han Hongbing Ma Ping Zhang Tim Fingscheidt China United Network Communications Group Company Limited Beijing 100033China Beijing University of Posts and Telecommunications Beijing 100876China Institute for Communications Technology Technische Universitat BraunschweigBraunschweig 38106Germany

MPEG-4 High-Efficiency Advanced Audio Coding (HE-AAC) is designed for low bit rate applications, such as audio streaming in mobile communications. The HE-AAC audio codec offers a better coding efficiency since variable-length codes (VLCs) are adopted. However, HE-AAC has originally been designed for storage and error-free transmission conditions. For the transmission over bit error-prone channels, error propagation is a serious problem for the VLCs. Therefore, a robust HE-AAC decoder is desired, especially for mobile communications. In contrast to traditional hard-decision decoding, utilizing bit-wise channel reliability information, softdecision (SD) decoding has been known to offer better audio quality. In HE-AAC, the global gain parameter is coded with fixedlength codes (FLCs), while the scale factors and quantized spectral coefficients are coded with VLCs. In this work, we apply FL/SD decoding to the global gain parameter, VL/SD decoding to the parameters scale factors and quantized spectral coefficients. Especially, in order to apply VL/SD decoding to the quantized spectral coefficients, a new modified trellis representation in VL/SD decoding is proposed. An improved HE-AAC performance is clearly observed, with the support of both instrumental measurements and a subjective listening test.

关键词： variable-length soft-decision decoding HE-AAC trellis representation quantization spectral coefficients

基于节点子集和k阶信息截断的多元LDPC译码算法

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电子学报 2017年第8期45卷 1925-1930页

作者：孙友明陈海强黎相成万海斌覃团发华南理工大学电子与信息学院广东广州510640 广西大学物理科学与工程技术学院广西南宁530004 广西多媒体通信与网络技术重点实验室培育基地/广西高校多媒体通信与信息处理重点实验室广西南宁530004 广西大学计算机与电子信息学院广西南宁530004

本文提出一种低复杂度的多元LDPC译码算法,从以下两个方面降低复杂度:(1)提出一种节点截断策略,构造处理/非处理校验节点子集,使得一部分足够可靠的校验节点不进行信息更新,从而减少运算量;(2)针对处理校验节点子集,本文进而提出一种k... 详细信息

本文提出一种低复杂度的多元LDPC译码算法,从以下两个方面降低复杂度:(1)提出一种节点截断策略,构造处理/非处理校验节点子集,使得一部分足够可靠的校验节点不进行信息更新,从而减少运算量;(2)针对处理校验节点子集,本文进而提出一种k阶信息截断准则,对trellis图上的边和状态进行划分.在迭代递归过程中,只有"活"的状态/边才参与运算,可进一步降低校验节点的计算量.仿真表明,本文算法的译码性能与现有的几种EMS改进算法非常接近;在译码复杂度方面,不管对高阶域还是低阶域的多元LDPC码,本文算法的复杂度都是最小的.

关键词：多元LDPC码 trellis 节点子集信息截断

A Novel Decoding Method for Non-Binary TCM Codes

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Communications and Network 2014年第1期6卷 22-28页

作者： Riyadh A. Al-Hilali Abdulkareem S. Abdallah Raad H. Thaher College of Engineering Al-Mustansiriyah University Baghdad Iraq College of Engineering Al-Mustansiriyah University Baghdad Iraq College of Engineering Basrah University Basrah Iraq

A new non-binary decoding method, which is called Yaletharatalhussein decoding algorithm, is designed and implemented for decoding non-binary convolutional codes which is based on the trellis diagram representing the convolutional encoder. Yaletharatalhussein decoding algorithm outperforms the Viterbi algorithm and other algorithms in its simplicity, very small computational complexity, decoding reliability for high states TCM codes that suitable for Fourth-Generation (4G), decreasing errors with increasing word length, and easy to implement with real-time applications. The proposed Yaletharatalhussein decoding algorithm deals with non-binary error control coding of the convolutional and TCM codes. Convolutional codes differ from block codes in that a block code takes a fixed message length and encodes it, whereas a convolutional code can encode a continuous stream of data, and a hard-decision decoding can easily be realized using the Yaletharatalhussein algorithm. The idea of non-binary codes has been extended for symbols defined over rings of integers, which outperform binary codes with only a small increase in decoding complexity. The simulation results show that the performance of the nonbinary TCM-based Yaletharatalhussein algorithm outperforms the binary and non-binary decoding methods.

关键词： Convolutional Codes Coded Modulation (CM) trellis Code Modulation (TCM) Non-Binary Error Correcting Codes Groups Rings of Integers