LT码的性能分析及仿真

Analysis and Simulation Performance of LT Codes

LT码(Luby Transform Codes)属于喷泉码的其中一种,它是一类基于图的线性纠删码,其应用的信道环境是删除信道(BEC,Binary Erasure Channel)。这里主要介绍在二元删除信道模型下,LT码的4种度分布设计方法及,分析了短码长和长码长情况下的LT码在不同信道删除概率情况下的性能及比较。研究结果表明:在删除概率非常大的情况下,只要译码端接收到足够多的包都能以高概率译出原始数据包,只是产生的冗余度大,这里的结果将为系统选择不同参数的LT码提供参考。

LT codes（Luby Transform Codes） as one of the Fountain codes and a kind of graph-based linear erasure codes,and can be applicated under Binary Erasure Channel（BEC）.This paper gives the binary erasure channel model and describes the four design methods for LT codes degree distribution.The performance of LT code with short code length and long code length under the different channel deletion probabilities is analyzed and compared.The experimental results show that in the case of large deletion probability,so long as the decoder receives sufficient number of packets,the original data packet could be recovered with high probability.The research results given in this paper could serve as a reference for system to choose different LT code parameters.