点频干扰下GPS接收机捕获性能研究

Research of GPS Receiver Acquisition Performance under Single Frequency Interference

在GPS接收机信号捕获原理的基础上,分析了点频干扰对接收机捕获性能的影响。给出了GPS C/A码接收机信号捕获的数学模型,计算得出GPS C/A码接收机的平均捕获时间与捕获时间方差,推导出点频干扰与噪声的功率谱密度,从而得到检测概率和虚警概率的表达式,仿真结果表明,当点频干扰功率超过一定的值时,会导致GPS接收机捕获性能恶化。

Based on the acquisition principle of GPS receivers, effect of single frequency interference on GPS C/A code receiver acquisition performance is analyzed. In this paper, a detailed mathematical model for signal acquisition based on the analysis of the GPS re- ceivers＇ circuit, average acquisition time and its variance are calculated, the Power spectrum density of single frequency interference and noise are deduced, thereby the expressions of detecting probability and false alert probability are concluded. The result d computer simulalion indicates that acquisition penformance badly worsened when the power of single frequency interference exceed a certain value.