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Performance evaluation of multicast relay network using LDPC and convolutional channel codes along-with XOR network coding

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 122-128页

作者： Tariq Aziz Nasir Saleem Muhammad Iqba School of Information and Communication Beijing University of Posts and Telecommunications

In this paper, we have compared the performance of joint network channel coding （JNCC） for multicast relay network using low density parity check （LDPC） codes and convolutional codes as channel codes while exclusive or （XOR） network coding used at the intermediate relay nodes. Multicast relay transmission is a type of transmission scheme in which two fixed relay nodes contribute in the second hop of end-to-end transmission between base transceiver station （BTS） and a pair of mobile stations. We have considered one way and two way multicast scenarios to evaluate the bit error rate （BER） and throughput performance. It has been shown that when using XOR network coding at the intermediate relay nodes, the same transmission becomes possible in less time slots hence throughput performance can be improved. Moreover we have also discussed two possible scenarios in the proposed system model, in which both diversity and multiplexing gain has been considered. It is worth notifying that BER and throughput achieved for LDPC codes is better than convolutional codes for all the schemes discussed.

关键词： cooperative relaying network coding multicast relay networks LDPC codes convolutional codes

Construction of type-Ⅱ QC-LDPC codes with fast encoding based on perfect cyclic difference sets

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Optoelectronics Letters 2017年第5期13卷 358-362页

作者：李玲香李海兵李季碧江华 School of Electronics and Information Engineering Hunan University of Science and Engineering BNP Paribas College of Communication and Information Engineering Chongqing University of Posts and Telecommunications Key Laboratory of Granular Computing Minnan Normal University

In view of the problems that the encoding complexity of quasi-cyclic low-density parity-check(QC-LDPC) codes is high and the minimum distance is not large enough which leads to the degradation of the error-correction performance, the new irregular type-Ⅱ QC-LDPC codes based on perfect cyclic difference sets(CDSs) are constructed. The parity check matrices of these type-Ⅱ QC-LDPC codes consist of the zero matrices with weight of 0, the circulant permutation matrices(CPMs) with weight of 1 and the circulant matrices with weight of 2(W2CMs). The introduction of W2CMs in parity check matrices makes it possible to achieve the larger minimum distance which can improve the error-correction performance of the codes. The Tanner graphs of these codes have no girth-4, thus they have the excellent decoding convergence characteristics. In addition, because the parity check matrices have the quasi-dual diagonal structure, the fast encoding algorithm can reduce the encoding complexity effectively. Simulation results show that the new type-Ⅱ QC-LDPC codes can achieve a more excellent error-correction performance and have no error floor phenomenon over the additive white Gaussian noise(AWGN) channel with sum-product algorithm(SPA) iterative decoding.

关键词： convolutional codes Encoding (symbols) Error correction Errors Gaussian noise (electronic) Iterative decoding Iterative methods Matrix algebra Satellite communication systems Set theory Signal encoding Turbo codes White noise

A novel construction method of QC-LDPC codes based on the subgroup of the finite field multiplicative group for optical transmission systems

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Optoelectronics Letters 2016年第1期12卷 61-64页

作者：袁建国周光香高文春王永林金朝庞宇 Key Laboratory of Optical Communication and Networks Chongqing University of Posts and Telecommunications

According to the requirements of the increasing development for optical transmission systems,a novel construction method of quasi-cyclic low-density parity-check(QC-LDPC) codes based on the subgroup of the finite field multiplicative group is ***,this construction method can effectively avoid the girth-4 phenomena and has the advantages such as simpler construction,easier implementation,lower encoding/decoding complexity,better girth properties and more flexible adjustment for the code length and code *** simulation results show that the error correction performance of the QC-LDPC(3 780,3 540) code with the code rate of 93.7% constructed by this proposed method is excellent,its net coding gain is respectively 0.3dB,0.55dB,1.4dB and 1.98dB higher than those of the QC-LDPC(5 334,4 962) code constructed by the method based on the inverse element characteristics in the finite field multiplicative group,the SCG-LDPC(3 969,3 720) code constructed by the systematically constructed Gallager(SCG) random construction method,the LDPC(32 640,30 592) code in ITU-T G.975.1 and the classic RS(255,239) code which is widely used in optical transmission systems in ITU-T G.975 at the bit error rate(BER) of ***,the constructed QC-LDPC(3 780,3 540) code is more suitable for optical transmission systems.

关键词： Bit error rate convolutional codes Error correction Inverse problems Light transmission Optical communication Satellite communication systems Transmissions

Improving the Structure of Multiple Dimension Turbo codes Using Multiple Identical Component Encoders

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Wuhan University Journal of Natural Sciences 2010年第4期15卷 330-334页

作者： WANG Zhenghai1, TIAN Mao1, WANG Yuhao2 1. School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China 2. School of Information Engineering, Nanchang University, Nanchang 330031, Jiangxi, China School of Electronic Information Wuhan University Wuhan Hubei China School of Information Engineering Nanchang University Nanchang Jiangxi China

In this paper,we propose an improved structure for M-dimension ( M ≥ 2)turbo codes using M identical component encoders. The presented structure only applies single recursive convolutional encoder to encode M interleaved versions of infor-mation sequence and single tail sequence to operate termination. For the commonly used two-dimension (M = 2) turbo codes,two cascade soft input soft output (SISO) decoders are detailed to de-code the corresponding codes. With the two cascade SISO decod-ers,this coding structure obviously outperforms traditional turbo codes at high code rates,especially,about 0.3 dB gain can be ob-tained at code rate 0.9 in additive white Gaussian noise channel with quadrature phase shift keying modulation. This makes the proposed coding structure very attractive for future radio commu-nication systems with high throughput requirements.

关键词： turbo codes concatenated codes convolutional codes soft input soft output (SISO)

Blind recognition of k/n rate convolutional encoders from noisy observation

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Journal of Systems Engineering and Electronics 2017年第2期28卷 235-243页

作者： Li Huang Wengu Chen Enhong Chen Hong Chen Computer Science and Technology University of Science and Technology of China Hefei 230026 China Graduate School China Academy of Engineering Physics Beijing 100088 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noisy context based on Walsh-Hadamard transformation and block matrix (WHT-BM). The proposed algorithm constructs a system of noisy linear equations and utilizes all its coefficients to recover parity check matrix. It is able to make use of fault-tolerant feature of WHT, thus providing more accurate results and achieving better error performance in high raw bit error rate (BER) regions. Moreover, it is more computationally efficient with the use of the block matrix (BM) method. © 2017 Beijing Institute of Aerospace Information.

关键词： Cognitive radio Convolution convolutional codes Error correction Hadamard matrices Hadamard transforms Linear transformations Mathematical transformations Matrix algebra Signal encoding

On The Burst Properties of P-TC8PSK Decoder

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On The Burst Properties of P-TC8PSK Decoder

1998 International Conference on Communication Technology

作者： Wang Hua Gong Chaohua Kuang Jingming Beijing Institute of Technology

ISBN: (纸本)7800908275

＜正＞P-TCM（Pragmatic Trellis-coded Modulation） has received much attention in recent years and has been proposed for high-speed satellite data *** order to obtain the burst properties of the P-TC8PSK decoder,AGM（Asymptotic Geometric Model） was employed to model the error sequence produced by *** of the wide distribution of the error sequence,it is difficult to let each error sequence with different length as a state of the model and we merge error sequnces within a range of certain length into a *** obtained are several important parameters which help the design of interleaver and estimation of the whole *** was performed to verify the correctness of the *** results show the model can well represent the burst properties of the decoder.

关键词： Viterbi Decoder Pragmatic TCM Channel Coding convolutional codes

Self-correcting FSM Architecture Implementation Based on convolutional Code

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Self-correcting FSM Architecture Implementation Based on Con...

2006 8th International Conference on Solid-State and Integrated Circuit Technology

作者： Ming Li Jian-Wei Gu Jia-Lin Cao Feng Ran Yong Shao Microelectronic Research and Development Center Shanghai University

ISBN: (纸本)1424401607

＜正＞We discuss the use of convolutional code to implement single fault tolerant Finite State Machines （FSMs） in VLSI *** order to correct the fault,we propose a novel scheme which can simultaneously detect and correct errors occurred in FSM *** design a key decoder behind the *** error state will be corrected and sent back to the FSM,so that the concurrent error in the current state is detected and ***,we realize the IP core of the fault tolerant module by SMIC 0.25μm CMOS technology and also simulate its function in FPGA.

关键词： convolutional codes Error correction Fault tolerance CMOS technology Automata Very large scale integration Circuit faults Electrical fault detection Fault detection Decoding

Antenna/Relay Selection for Coded Wireless Cooperative Networks

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Antenna/Relay Selection for Coded Wireless Cooperative Netwo...

2008 IEEE International Conference on Communications(ICC 2008)

作者： Mohamed Elfituri Ali Ghrayeb Walaa Hamouda Department of Electrical and Computer Engineering Concordia University

In this paper,we consider distributed coding for wireless cooperative networks with antenna/relay selection. The aim of this of work is to find ways to improve the reliability of the source-relay link in an effort to maintain the diversity order available in the system. To this end,we propose to use antenna selection at the relay node whereby the antenna with the best instantaneous received signal to noise ratio is selected. This assumes that the relay node is equipped with multiple antennas,but only one radio frequency （RF） chain is employed. The concept of antenna selection can be extended to relay selection. That is,among the available relay nodes,the one with the best source-relay link reliability is selected. Assuming decode-andforward （DF） relaying,we analyze the antenna/relay selection in conjunction with a previously proposed distributed coded cooperation scheme based on convolutional codes. Specifically,we derive an upper bounded expression for the symbol error rate assuming M-ary phase shift keying （M-PSK） transmission. Our analytical results show that the maximum diversity order of the system is maintained for the entire range of bit error rate of interest,unlike the case without antenna selection. Several numerical and simulation results are presented to demonstrate the efficiency of the proposed scheme.

关键词： Relays Receiving antennas Radio frequency Maintenance Signal to noise ratio Decoding convolutional codes Error analysis Phase shift keying Bit error rate

Robust Multilevel Coding Design using Soft Decision Decoding

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Robust Multilevel Coding Design using Soft Decision Decoding

2000 International Conference on Communication Technology(WCC2000·ICCT2000)

作者： Dong-Feng Yuan Ai-Fen Sui Zhi-Gang Cao Electrical Engineering Department Shandong University Electrical Engineering Department Tsinghua University

ISBN: (纸本)0780363949

＜正＞Based on Capacity Rule and Block Partitioning strategy,a robust Multilevel Coding （MLC） scheme is proposed for AWGN and Rayleigh fading *** convolutional codes using soft or hard decision Viterbi decoding are selected as component *** considerable performance gains over uncoded 4ASK system are demonstrated by computer simulation and the results can present some references for the optimum criterion of Multilevel Coding design.

关键词： Viterbi decoding convolutional codes Rayleigh channels AWGN channels optimisation robust multilevel coding soft decision decoding capacity rule block partitioning AWGN channels Rayleigh fading channels punctured convolutional codes hard decision decoding Viterbi decoding performance optimization