基于随机置换展开与停止集的LT码联合编译码算法

针对短码长LT码(码长在103以下)的随机编码方式,需要较高的编码冗余才能保证一定的译码性能的问题。设计了一种基于限制Tanner图连接边随机关系的随机置换展开编码算法,可以实现在较小编码冗余开销下提高短码长LT码的可译码概率。在此基础上,针对短码长LT码的传统BP译码算法效率不高的问题,充分利用BP算法译码失败的停止集剩余信息,设计了采用上述编码算法的短码长LT码的停止集高斯译码算法,可以获得接近最大似然译码的性能。仿真结果表明,所提出的编译码联合算法有效降低了短码长LT码满足10 4译码失败概率时所需的编码冗余开销。

Novel joint encoding/decoding algorithms of LT codes based on random permute egde-growth and stopping set

Since LT codes adopt the random encoding method,high coding overheads were required for a stable recovery probability of information.a random permute edge-growth-based coding algorithm was proposed, which could enhance the decoding probability of LT code through restricting the random connections between random permutation edges in the Tanner graphs.With this proposed coding algorithm, a decoding algorithm based on stopping set Gaussian elimination was proposed, which efficiently used the redundancy information in the stopping set after the belief propagation decoding.As a result, this decoding scheme could approach the performance of maximum-likelihood decoding.The simulation results show that, the proposed joint design on coding/decoding schemes could obviously reduce the overheads of such short length LT codes as 10＜sup＞3＜/sup＞, while achieve the decoding failure rate of 10＜sup＞- 4＜/sup＞.