BDS-3/BDS-2与BDS-3数据无电离组合PPP定位性能比较分析

Comparative analysis of ionosphere-free combination precise point positioning performance for BDS-3/BDS-2 and BDS-3 data

针对北斗系统当前BDS-3/BDS-2与BDS-3数据的PPP定位性能比较分析比较少,在建立北斗无电离层组合PPP定位模型基础上,详细推导了北斗PPP星间单差无电离层组合模糊度固定算法实现流程。基于Visual Studio 2022开发平台,利用C/C++编程语言,设计和开发了一种北斗PPP定位分析软件(BDS_PPP),用于比较分析BDS-3/BDS-2与BDS-3数据无电离层组合PPP定位性能。实验选取北京某CORS网中3个站(TST、DSK、LFZ)2023年155 d UTC 8:00—12:00连续4 h的B1I/B3I数据进行PPP定位性能比较分析。结果表明:BDS-3/BDS-2和BDS-3数据,无电离层组合PPP的固定解收敛时间和定位精度均优于浮点解定位,其中BDS-3/BDS-2与BDS-3数据的无电离层组合PPP定位收敛后模糊度固定成功率均在95%以上,且获得了平面RMS优于2 cm、点位RMS优于5 cm的PPP固定解定位精度;浮点解和固定解,BDS-3/BDS-2数据无电离层组合PPP定位的收敛时间均优于BDS-3数据,在定位精度上基本相当。

In view of the fact that BDS system currently providing BDS-3/BDS-2 combined service,the comparative analysis of PPP positioning performance for BDS-3/BDS-2 and BDS-3 data is still relatively scarce.In this paper,based on the establishment of the BDS ionosphere-free combination PPP positioning model,an implementation flowchart of integer ambiguity resolution algorithm for BDS PPP single-difference between-satellites ionosphere-free combination is deduced in detail.The BDS PPP positioning analysis software(short as BDS_PPP)using C/C++programming language based on Visual Studio 2022 development platform is designed and developed applied to compare and analyze the positioning performance of ionosphere-free combination PPP for BDS-3/BDS-2 and BDS-3 data.The B1I/B3I data from three stations(TST,DSK,and LFZ)in a CORS network in Beijing for 155 d UTC 8:00—12:00 for 4 consecutive hours in 2023 are selected for the positioning performance analysis,the results show that the convergence time and the positioning accuracy of ionosphere-free combination PPP fixed resolution are better than the float resolution positioning for not only BDS-3/BDS-2 data but also BDS-3 data,in which the integer ambiguity resolution success rate is 95%above after the positioning convergence of ionosphere-free combination PPP for both of BDS-3/BDS-2 and BDS-3 data,meanwhile the positioning accuracy of BDS PPP fixed resolution is better than 2 cm in the horizontal-RMS and 5 cm in the point-RMS respectively.For both float resolution and fixed resolution,the ionosphere-free combination PPP positioning in terms of convergence time for BDS-3/BDS-2 data is better than for BDS-3 data,while the positioning accuracy is basically comparable.