摘要
针对航天测控通信系统传输距离远,信道噪声干扰大等特点,研究了一种适用的LT编译码方案。基于对译码过程中预处理集分析给出的最优度分布理论模型,提出了一种混合型度分布函数。该函数为一种次优度分布,综合了部分常用度分布函数的优点,可有效提高编译码性能。优化后的LT编译码方案在航天测控系统中的应用进行了仿真,结果表明:译码效率提高了16.67%,且保持了良好的编码增益,适于系统的应用需求。
A LT code was proposed according to the characteristics of long transmission distance and large channel noise in space TT＆C communication system in this paper. Based on a theoretical model for optimal degree distribution analyzed in preprocessing set in the decoding, a hybrid degree distribution, which was a suboptimal degree distribution with high coding and decoding performance, was put forward on the basis of conventional degree distributions. The application of modified LT code in TT＆C system was obtained through simulation. The simulation results showed that the decoding efficiency was raised by 16. 67% with well decoding performance meeting the system demand.
出处
《上海航天》
2014年第2期47-51,68,共6页
Aerospace Shanghai
关键词
航天测控通信
LT码
度分布函数
Space TT＆C communication
LT Code
Degree distribution
