The Influence Of BDS Different Constellation On The Estimation Of Precise Point Positioning Parameters

The BDS developed by our country not only includes the medium earth orbit satellite(MEO),but also the geostationary orbit satellite(GEO)and the inclined geosynchronous satellite orbit(IGSO).Analysis of BDS satellite constellation of different effects on PPP parameter estimation,can improve the theoretical system of PPP for BDS,convenient to choose the appropriate BDS constellation for PPP,and provide reference for the real-time weather forecast,high precision navigation and positioning application.In this paper,the basic theory of PPP and the related technologies of multi system combination PPP are studied.At the same time,the different error sources,such as tropospheric delay are analyzed.Based on CORS network measured data and MGEX precise orbit and clock products for different BDS/GPS constellation combination of static and dynamic PPP experiments,discussing advantages and disadvantages of different combinations from the positioning accuracy and ZTD estimation accuracy.The statistical results show that:in the constellation BDS dual mode,MEO/IGSO is the best;in BDS and GPS single sign combination mode,IGSO/GPS is the best;in the BDS double constellation and GPS combination mode,MEO/IGSO/GPS is the best;BDS and GPS constellation than the full constellation combination mode.It is concluded that the IGSO satellite has a very important contribution on the positioning and ZTD estimation.