GPSRAIM算法中的多异常值探测方法

GPS Outliers Detection and Identification in RAIM

讨论了通过最小二乘法求解GPS观测方程中残差和异常值的特性,推导并改进了利用最小二乘残差探测卫星数据异常值的方法。通过分析可知,尽管残差和异常值存在线性关系,但异常值并不能通过残差来确定,一些残差可能使异常值为零。通过将异常值以及异常值的个数全部转换为最小值的方法可以有效探测多个异常值。根据码信号的电离层和对流层延迟的正值特性,可以将探测出的多个异常值进行约束,从而较好地解决异常值探测结果的多值性问题。算例的结果证明,此方法能够可靠探测出3个异常值。

The property of residuals and outliers was discussed by calculating GPS observation with the least square method.And then the least square method was deduced and improved.Though there was a linearization between the residual and outlier,outlier was not be able to get from residual,and some residuals made the outliers to be zero.Multi-outliers was detected effectively by transforming not only the outlier but also its numbers to minimum value problem.Outliers was constrained positive values because the ionosphere and troposphere delays were positive in code signal,and then the multiple values problem was resolved perfectly.The illustration proved that 3 outliers was able to detected by the improved algorithm.