LDPC码在高动态环境卫星通信中的应用

Application of LDPC Codes in High Dynamic Satellite Communications

高动态环境卫星通信系统中,通信终端的高速机动会导致卫星通信链路中断,从而引起一定程度的突发式数据丢失。主要针对高动态环境下的数据包丢失问题进行研究,提出将二元突发删除信道模型引入高动态环境中,详细介绍了删除信道下LDPC码的迭代译码和最大似然算法的译码原理,采用对码字进行预编码和信道编码方法,使得可以利用LDPC码完成数据包恢复。仿真结果表明,在一定数据丢包门限以内,LDPC码能够有效恢复出丢失数据包。

In satellite communication systems under high dynamic environment,the rapid motion of communication terminals will lead to the interruption of satellite communication links,which can cause the burst data loss. Our study focuses on the data loss issue under high dynamic environment,the binary burst erasure channel is introduced in this paper,and the principles of iterative decoding and maximum likelihood algorithm for LDPC codes over the erasure channel are illustrated. Then precoding and channel coding are applied to the codes,which can ensure that the LDPC codes can be used for packets recovering. The simulation results show that,within a certain range of numbers for packets loss,the LDPC code can effectively recover all the lost packets.