导航星座星间链路信号自适应捕获方法

摘要

In view of the signal dynamic characteristics and working mechanism of inter-satellite links in navigation constellation,an adaptive acquisition algorithm assisted by the navigation data is introduced.The proposed method makes use of the navigation data to calculate the time-delay,Doppler frequency and signal to noise ratio of the received signal.Based on the results,the search area,non-coherent times and threshold of sig-nal acquisition are adjusted adaptively to reduce acquisition time while improving acquisition performance.Final-ly,the effectiveness of the proposed algorithm is proved by the real orbit data of the global positioning system.%针对导航星座星间链路信号动态特性和工作特点，提出了一种基于星历辅助的自适应捕获方法。该方法利用导航卫星自有的导航电文对接收信号到达时延、多普勒频移和信噪比进行估计，根据估计结果自适应调整信号捕获的搜索范围、非相干累加次数和判决门限，以减少捕获时间、提高捕获性能。给出了自适应捕获的设计思路和流程，并结合全球定位系统真实轨道数据进行了仿真。仿真结果进一步证明了所提方法的有效性。