机载 GPS 接收机软故障检测方法的研究

摘要

针对 Wald 序贯概率比法检测机载 GPS 接收机软故障实时性差的缺点，提出了一种改进的序贯 Bayes 检测方法。该方法在检测过程中不断对检测统计值进行修正，在极大地减小检测机载 GPS 接收机软故障时延的同时，还使得检测决策的平均风险最小。仿真结果表明，改进的序贯 Bayes 检测方法相比于修正的 Wald 序贯概率比方法，可以更加快速地检测出机载 GPS 接收机的软故障，表明这种改进方法具备良好的实时特性，从而降低了机载 GPS 接收机的误警率，使其具备更高的可靠性和稳定性。%Considering that the Wald Sequential Probability Ratio Test (SPRT) has poor real-time performance for detecting the soft failure of the airborne GPS receiver,we proposed a revised sequential Bayesian detection method.The method can modify the test statistics continually during the detection ,thus can not only reduce greatly the testing time delay of the airborne GPS receiver soft failure,but also has minimum risks for decision-making of test.The simulation results show that: compared with the Wald SPRT method,the improved sequential Bayesian method can detect the soft failure of the airborne GPS receiver more quickly, which indicates that the method possesses a fine real -time performance.Furthermore,the method can decrease the probability of false alarm,so the airborne GPS receiver will have high reliability and stability .