用于识别两颗故障卫星的RAIM算法

提出了一种可以识别两颗故障卫星的接收机自主完好性监测算法.将最优奇偶矢量法应用于两颗故障卫星识别,指出由于故障偏差可能会抵消而使得正确识别率较低.对最优奇偶矢量法进行了改进,利用对单颗卫星故障敏感的最优奇偶矢量对所有可能的两颗故障卫星组合分别构造两个新的奇偶矢量,用于两颗故障卫星的检测和识别.计算机仿真结果显示,改进后的算法与直接利用最优奇偶矢量法相比,可以显著提高两颗故障卫星正确识别率,识别率可超过90%.同时,改进算法的奇偶矢量构造方法简单,计算量将减少90%以上,更有利于工程实现.

RAIM algorithm for identifying simultaneous two-faulty satellites

A new receiver autonomous integrity monitoring(RAIM) algorithm was proposed for identifying simultaneous two-faulty satellites.The optimal parity vector method was studied,and the results showed that the fault of one satellite may counteract the fault of the other satellite,which reduced correct identifying ratio greatly.Therefore a new approach was developed based the optimal parity vector method.For every possible two-faulty satellites combination,two new parity vectors were constructed for detecting and identifying simultaneous two-faulty satellites,using the parity vectors which were sensitive to designated satellite failure.Computer simulation results show that the correct identifying ratio of using new method is higher than that of using the optimal parity vector method,under the condition of simultaneous two-faulty satellites.With the new algorithm,the correct identifying ratio will be higher than 90%.Moreover,the new method simplifies the processing of constructing parity vector,and reduces more than 90% of the computational burden.So the new method is better for engineering implementation.