非规则LDPC码在RICE信道中的性能分析  

Performance of Irregular LDPC Codes on Rician-Fading Channels

作　　者：林家儒[1] 吴伟陵[1] 

机构地区：[1]北京邮电大学信息工程学院,北京100876

出　　处：《电子学报》2005年第1期43-46,共4页Acta Electronica Sinica

基　　金：国家自然科学基金 (No 60 2 72 0 52 );国家 863项目 (No .2 0 0 1AA1 2 30 1 6

摘　　要：本文对非规则LDPC码在RICE信道的性能进行了分析和仿真 ,修正了BP译码算法 ,证明了RICE信道满足对称性 ,给出了RICE信道译码稳定性条件 ,推导出了RICE信道的Shannon容量限 ,采用VC编程对码长N =4 95 12和 30 72进行了仿真 ,同时与同码长的Turbo码进行了比较 ;仿真结果表明LDPC码在码长N =4 95 12、码率R =1/3时 ,与Shannon限相差 1dB以内、在低信噪比时其性能优于Turbo码 ,以及LDPC码本身有很好的交织特性和抗衰落的能力 ;这进一步表明了LDPC码在包括RICE信道在内的各种信道中的性能都是非常优良的 .This paper analyzes and simulates the performance of irregular low density parity check (LDPC) codes on Rician fading channels and the others, and modifies BP decoding algorithm, proves the symmetry and shows the stability conditions on Rician channels, calculates the Shannon limit of Rician channels. Using Visual C++ we simulate the performance with code word length N = 3072 and 49152. The simulation results indicate that when N = 49152, code rate R = 1/3, the distance from Shannon's limit are 0.67 dB, 0.72 dB and 0.91 dB for AWGN, Rician and Rayleigh channels, respectively, LDPC codes having nice interleaving performance and anti-fading capability, and better performance of LDPC than Turbo codes in some area of SNR. Therefore the performance of LDPC codes is also very effective on all kind of channels, including Rician channels.

关 键 词：LDPC 衰落信道 RICE信道 

分 类 号：TN91[电子电信—通信与信息系统]