一种应用于深空通信的微弱信号捕获算法

针对低信噪比、高动态条件下深空测控通信信号捕获概率低以及复杂度较高的问题，首先分析了深空测控通信信号捕获的难点以及信号循环平稳特性，然后在此基础上提出了一种基于循环相关的新算法。计算机仿真结果证明新算法捕获门限达24 dBHz，适应频率动态达800 Hz/s；新算法较传统的捕获算法，在相同门限条件下的频率动态适应范围提升了约两个数量级。该方法已被应用于我国第一个深空测控站的建设，工作性能稳定可靠，有效地解决了低信噪比下深空站抑制载波信号的捕获问题。

A weak signal acquisition method for deep space communication

The characteristics of low signal-to-noise ratio(SNR) and high dynamic in deep space communications would result in high complexity and low acquisition probability in telemetry tracking and command(TT&C) signals acquisition process. Firstly, the difficulty of signal acquisition and cyclo-stationarity of TT&C signals are analyzed. And then, a new algorithm based on cyclic correlation detection is proposed. The simulation results show that acquisition threshold and dynamic range of the proposed algorithm reach 24 dBHz and 800 Hz/s,respectively. Compared with the traditional squaring method, the new algorithm can increase the frequency dynamic range up to two orders of magnitude at the same acquisition threshold. This method has been used in the development of China''s first deep space TT&C station.Engineering practice results verify that the algorithm performance is stable and reliable, and it is a good solution to low SNR suppressed-carrier TT&C signal acquisition problem.