起始点位置偏差对精密GPS差分定位影响的研究

从理论上讨论了起始点位置误差对ＧＰＳ基线解算精度的影响，并对实测资料进行了模拟计算，得到了与理论计算值相吻合的结果。指出：ＧＰＳ网中起始点的位置偏差不影响基线解的内部精度，但使ＧＰＳ基线解产生系统性偏差，偏差的大小与起始点位置偏差的大小成正比，与基线平均纬度的正切函数值成正比。文章最后，对在“ＳＡ”和“ＡＳ”技术影响下，进行高精度ＧＰＳ差分定位时，如何测定网中具有较高精度的ＷＧＳ８４坐标起始点问题，提出了建议。

Study on Impact of Origin Positioning Deviation of DGPS Precise Surveying

In this paper,the impact of the origin positioning deviation on precision of GPS baseline is discussed theoretically,simulated calculation of the GPS raw data is made and the result fits well with that calculated theoretically.The following conclusions could be drawn:the origin positioning deviation does not affect the internal accuracy but makes a systematic error that varies with the origin positioning deviation and tyB m(B m is a mean latitude of the baseline)to the result of baseline.Finally,suggestions are made as to how to get a more accurate WGS84 coordinates when carrying on DGPS(Differential GPS)precise surveying.