深空通信中继下行链路特性研究及仿真分析

A Study on the Characteristic of Relay Downlink in the Deep Space Exploration

在深空通信中,由于信号传输距离遥远,功率受限的下行链路信号衰减巨大。为解决上述问题,分析地球大气层和外层自由空间的传输特性差异,提出以地球同步轨道卫星为中继站的下行链路的构想,根据每一段链路特性的不同选择载波频率。仿真结果表明,中继链路可以提高信号传输的信噪比、增大信道容量、降低误码率,提高了深空通信下行链路的可靠性。

In the deep space communication,great attenuation of downlink signal is caused by the long distance of transmission.To solve this problem,the specialties of the earth aerosphere and outer space are analyzed,and an idea of relay downlink with a geosynchro- nous earth orbit satellite is put forward.Different frequencies are adopted according to the characteristics of different links.Relay downlink can achieve a higher ratio of signal-to-noise,increase the capacity of channel,reduce the bit error rate and enhance the reliability of down- link in the deep space communication.