一种用于深空通信的系统LT码

Systematic LT Code for Deep Space Communication

针对传统LT(Luby Transform)码用于深空通信时性能不理想的问题,通过重构LT码的二分图设计适用于深空通信环境的系统LT码,提出一种去环编码算法。采用外信息转移图分析系统LT码的收敛阈值,然后通过仿真试验评估系统LT码的性能。仿真结果表明,采用本文提出的编码方案的系统LT码能够明显降低错误平层,提高译码算法的性能。

The performance can be degraded when traditional LT （ Luby Transform） codes are used for deep space communications. In this paper the systematic LT codes are designed by reconstructing the bipartite graph and can be suitable for deep space communication en,;ironment. An encoding algorithm to eliminate cycles is proposed. The convergence threshold of the systematic LT codes is analyzed by using extrinsic information transfer chart. And then the performance of systematic LT codes is evaluated through a serial of simulation experiments. Simulations results show that the systematic LT codes adopting the proposed encoding algorithm can significantly degrade the error floor and improve the decoding algorithm performance.