差分改正数的更新率对定位精度的影响分析

介绍了GPS(Global Positioning System)定位的误差来源及差分的具体形式,描述了伪距定位及伪距差分定位的数学模型.分析了差分修正后的用户伪距残差和SA(Selective Availability)信号的关系,并从SA的时间相关特性出发,分析了伪距差分中差分改正数的更新率对定位精度的影响.最后,利用RTCM SC 104格式的电文1进行了不同更新率的实验,得出了具有实践意义的结论.

Influence Analysis of Differential Corrections Transmitting Cycle on Positioning Precision

The positioning error elements of GPS are described and the differential means are proposed in detail. The mathematics models of pseudo range position and pseudo range differential position are also introduced. The relationship between the corrected user pseudo range residue and SA signal is analyzed. Based on the temporal correlation of SA signal, a suitable transmitting cycle of correction is then acquired in the local differential method. The correction contains pseudo range correction and pseudo range rate correction, which are included in the RTCM SC 104 telegraphese 1. In final, the practical conclusion is provided via many pseudo range differential position experiments in a fixed point and many different correction transmitting cycles.