GPS多星故障识别改进算法的仿真研究

Simulation Study on Improved Algorithm of GPS Multi-Satellite Fault Identification

为了能够识别多颗卫星故障,提高卫星导航定位系统的可靠性,提出了一种专门针对多故障情况的MHSS(多假设分组)算法。首先介绍了MHSS算法的基本原理,并对其仿真,表明其较传统算法更能满足更高导航完好性的需求;然后提出了MHSS-FDE改进算法,该算法与传统算法比较类似,需要计算检测门限进行有/无故障判决,将MHss方法中不受伪距测量影响的项排除,构造假设验证法的识别判别函数进行故障卫星识别;最后以多颗故障卫星条件为例对改进的MHSS-FDE算法故障识别率进行计算机仿真,并与现有的可用于多星故障识别的FDE算法进行仿真比较,结果显示:改进的MHSS-FDE算法具有较高的故障识别率。

In order to identify multiple satellites failure,improve the reliability of satellite navigation and positioning system,a special case for multi-fault MHSS（multiple hypothesis grouping） algorithm is presented.Firstly,the basic principle of MHSS algorithm is introduced and its simulation indicates that it better meets the needs of higher navigation integrity than conventional.Then,the MHSS-FDE improved algorithm is proposed,which is similar to the traditional method.It needs to calculate the detection threshold to adjudge with/without fault,the items not affected by pseudo range measurement method in MHSS are excluded,the identification discriminate function based on hypothesis testing method is constructed to identify the fault satellites.Finally,taking multiple fault satellite conditions as examples,the fault detection rate of improved MHSS-FDE algorithm for different satellites is simulated.Compared with the existing available FDE algorithm for multi-satellite fault identification,the improved MHSS-FDE algorithm has higher fault recognition rate.