北斗双频和三频相对定位精度分析

Relative Positioning Accuracy Analysis of Beidou Dual-frequency and Tri-frequency

针对我国北斗相对定位性能,推导了北斗双频与三频相对定位模型,并基于IGS跟踪站组成的超短基线与短基线,分析了北斗双频与三频相对定位三维精度与模糊度固定情况。经研究发现,双频组合B1/B2组合与B1/B3组合下相对定位精度与模糊度固定率相当,B2/B3组合观测噪声太大,模糊度固定率与定位精度较低,不适合进行高精度相对定位,三频组合B1/B2/B3组合相比于双频组合相对定位精度有较明显提升,其中超短基线相对定位精度提升幅度明显优于短基线。

Considering the relative positioning performance of Beidou in China,this paper derived the relative positioning model of Beidou dual-frequency and tri-frequency.And based on the ultra-short baseline and short baseline composed of IGS tracking stations,the relative positioning three-dimensional accuracy and ambiguity of Beidou dual-frequency and tri-frequency were analyzed.After research,it is found that the relative positioning accuracy and ambiguity fixed rate are equivalent under the dual-frequency combination B1/B2 and B1/B3.The observation noise of the B2/B3 combination is too large,and the fixed ambiguity and positioning accuracy are low,which is not suitable for high accuracy relative positioning.The relative positioning accuracy of the three-frequency combination B1/B2/B3 is significantly improved compared to the dualfrequency combination,and the relative positioning accuracy of the ultra-short baseline is obviously better than that of the short baseline.