摘要
根据Galileo系统的完好性概念,空间信号误差(SISE)是由卫星星历和卫星钟差引起的距离域上的最大误差。SISMA是空间信号监测精度,SISE真实值和SISE估计值之差服从一个分布,这个分布将由高斯分布的最小标准偏差限定,即为SISMA[2]。从SISMA的计算公式看,决定其结果的因素有3个:1)最差用户位置单位矢量ajWUL;2)监测站观测卫星的几何条件;3)协方差阵对角元素的取值。因此本文将通过改变这3个条件完成3个试验,将试验结果进行比对分析,判断这3个因素对SISMA结果的影响。
According to the integrity concept of Galileo system, signal in space error （SISE） is the maxi- mum error in distance sense caused by the difference between the satellite ephemeris and the satellite clock. The signal in space monitoring accuracy （SISMA） is the difference of the true value and the estimation of SISE , and it is a random variable determined by the minimum standard deviation of a Gaussian distribu- tion. From the expression of the estimation of SISMA, there are three factors of impacting the estimation re- salts ： 1 ） The unit vector of the worst user position a^j_WUL ; 2） The geometry condition of the monitor station and the observed satellite ; 3 ） Values of diagonal elements of observation covariance matrix. In this paper, experiments are done by changing the three factors above, and the results are compared and effects of these factors are analyzed.
出处
《航天控制》
CSCD
北大核心
2012年第6期38-42,49,共6页
Aerospace Control
基金
863多模卫星导航系统完好性关键技术研究(2008AA12Z308)
关键词
完好性
空间信号误差
空间信号监测精度
最差用户位置
Integrity
Signal in space error（ SISE ）
Signal in space monitoring accuracy（ SISMA ）
Worstuser location（WUL）
