“北斗一号”卫星信标不同通道信号互扰分析和解决方法

Mutual Coupling Effects Analysis and Solution of Different Channel COMPASS-1 Signals

分析了"北斗一号"信号强弱信号码自干扰对弱信号捕获所构成的影响,并将在GPS中行之有效的一种连续干扰取消(SIC)方法应用于"北斗"。模拟及实测结果表明:强弱信号强度相差高于15 dB时,"北斗一号"信号码自干扰已经不可忽视;当强弱信号强度相差超过一定程度,弱信号会陷于完全的失捕或是误捕。采用SIC方法通过去除强信号解除码自干扰影响,使强信号下弱信号捕获得以实现且效果明显。

This paper presents an analysis of Kasami code cross-correlations, and its impact on the acquisition of weak signals when coexisting with strong signals. A SIC（Successive Interference Cancellation） method is introducod to mitigate the interference to allow successful acquisition of the weak signals. Test result shows that cross-correlation effect cannot be ignored when strong signals are 15dB higher than the weak signals. The higher cross-correlation may result in complete loss or false acquisition of weak signals. Using SIC method, the weak COMPASS-1 signals can be captured successfully.