Comparative Analysis And Research Of Multi-system Network RTK Technology In Yunnan Tibetan Areas

At present,there are many satellite navigation and positioning systems in the world such as GPS of the United States,GLONASS of Russia,and BDS of China.With the coexistence of various satellite systems,the multi-system network RTK positioning technology has become a research hotspot and GNSS positioning technology.Based on the theory of multi-system satellite positioning and navigation technology and methodology,this paper studies the positioning accuracy of GPS,GLONASS and BDS satellite network positioning system RTK technology in Yunnan Tibetan areas,and the Yunnan Tibetan areas with high altitude,high cold and high variation.CORS system research and comparative analysis of multi-system network RTK positioning technology,the research results have certain practicability and economic value,and have certain practical significance for the development of surveying and mapping society in Yunnan Tibetan areas.The comparative analysis of the multi-system network RTK technology can be divided into two parts: one is to study the DQCORS system,the geoid-like refinement and the independent coordinate system to ensure the accuracy and reliability of the multi-system network RTK technology in Yunnan Tibetan areas.Sexuality,for the comparative analysis of multi-system network network RTK technology to provide C-level points and known data support on the refinement point of the geoid;second,the accuracy of the satellite system network RTK in the C-level and refinement points Conduct a comparative analysis.After researching and analyzing the two parts,the following conclusions are drawn.(1)Research on the DQCORS system.This paper mainly studies the influencing factors of site selection of DQCORS system,and studies the impact of DQCORS system photovoltaic power supply and site drop on network RTK users.It is further verified that the DQCORS system can guarantee the accuracy of multi-system network RTK positioning results.At the same time,the DQORS system research results provide a comparison analysis of internal and external accuracy of C-level points for multi-system network RTK positioning.(3)Collecting and analyzing the topographic data,level data,GNSS observation data and gravity data in the surrounding areas of Yunnan Tibetan areas,and combining the mathematical model of gravity field to study the geoid of Diqing Prefecture.For the refinement test of the geoid surface,the accuracy of the elevation direction at the refinement point is provided for multi-system network RTK positioning.At the same time,the research results of the independent coordinate system provide the accuracy of the plane direction on the refinement point for multi-system network RTK positioning.(4)On the one hand,from the initialization time,the C-level point and the measured data on the refined point and the internal accuracy of the 24 h measured data,the GPS+GLONASS+BDS mode network RTK positioning result is optimal,and the GPS+GLONASS mode is excellent.On the other hand,in the GPS+BDS mode;on the other hand,the multi-system network RTK positioning technology is analyzed in the external precision of the C-level point and the geodetic level of the Yunnan Province.The GPS+GLONASS mode is optimal,GPS+GLONASS+BDS The mode is slightly better than the GPS+BDS mode.In addition,from the accuracy analysis of the different directions of the calculation results,the X direction of the different combined systems is better than the Y direction,and both are better than the H direction;the accuracy of the plane accuracy is better than that of the elevation direction,and the external plane meets the accuracy plane.The direction accuracy is slightly lower than the positioning accuracy of the path direction.