面向深空通信的中继协作喷泉码设计

针对未来深空超远距离通信无法建立有效的点对点链路及大路径损耗、大传播延时等难题，提出了一种基于中继协作网络模型下的喷泉编码转发方案。与现有的空间传输协议相比，喷泉码能够以较低的编译码复杂度为下行数据分组提供前向纠删保护，降低确认重传的次数，有效减少传输时延。在地球〖CD*2〗火星通信场景下，对中继编码协作转发方案的复杂度和能量开销进行了性能评估，并在理论上分析了中继卫星的位置对系统性能的影响。仿真结果表明，中继喷泉编码协作转发方案可有效节约深空环境下通信系统的能量开销。

Relay cooperation fountain codes for deep space communications

According to the difficulties of establishing effective point-to-point links,large path loss and propagation delay in extreme distance space communication,a novel fountain code-and-forward scheme is proposed based on the cooperative relaying network.Compared with the present automatic repeat-request transport protocols,fountain codes have forward error control ability to protect the down-link data packets,reduce retransmission times and shorten file delivery delay with lower complexity.Under the Earth-to-Mars communication scenario,the complexity and power performance of this scheme are evaluated,respectively.Additionally,the effect of the system performance by the position of relay satellites is theoretically analyzed.Simulation results reveal that the relay fountain coded cooperation forwarding scheme can save the energy expenditure of communication systems effectively in deep space environment.