多进制LDPC编码调制系统在衰落信道下的性能分析

多进制低密度奇偶校验（Low-Density Parity-Check,LDPC）码作为一种现代高效纠错码将会是RS码的一个很好替代码型。现代通信系统需要可靠且频谱有效的数据传输,针对多进制LDPC编码调制系统,文章分析和讨论了多进制LDPC编码调制系统在Ray-leigh和Rice衰落信道下的性能。引入了Rayleigh和Rice衰落信道模型,在此基础上建立了多进制LDPC编码调制系统,给出了迭代译码的初始化条件。仿真结果表明多进制LDPC码本身具有很好的交织和抗衰落特性,相比于二进制LDPC编码调制系统,多进制LDPC编码调制系统在衰落信道下的性能非常优良。

Performance of LDPC Coded Modulations over Fading Channels

Nonbinary low-density parity-check（LDPC） codes,as modern efficient error correcting codes,may be used to replace RS codes properly.A reliable and bandwidth-efficient data transmission with reasonable delay and good error performance is required in modern communication systems.The performances of nonbinary LDPC coded modulation systems over Rayleigh and Rice channels are analyzed and discussed.The Rayleigh and Rice fading channel models are introduced.The nonbinary LDPC coded modulation system is established based on the models,and the initialization of iterative decoding is presented.Simulation results show that nonbinary LDPC codes have good interleaving performance and anti-fading capability.Nonbinary LDPC coded modulations can achieve a better performance than binary LDPC coded modulations over fading channels.