PPP/SINS Tightly Integrated Usability Study

GNSS and SINS have strongly complementarity, to improve the navigation precision and reliability as well as the application of navigation technology is of great significance, is the realization of integrated navigation is an important solution. At present, using GNSS difference with SINS integrated navigation namely DGNSS/SINS integrated navigation system research is relatively mature, positioning accuracy is higher, which has been widely applied. DGNSS/SINS integrated navigation system, however, need to set up base station, improve the operation cost. Rover station and base station need to keep more than a dozen or even thousands of meters of distance, this is far away from the coast in Marine surveying and mapping. For inconvenient hypothetical reference station, the operation is difficult. And for within the scope of the larger part of the surveyed area need to set up multiple reference station,that increased the operation complexity. The PPP is the use of precise satellite orbit and satellite clock products to calculate a single receiver absolute positioning, compared with DGNSS, the PPP don't need to set up base station, there is no restricted by observation distance. Therefore,adopting the PPP/SINS integrated navigation system has a more broad application prospects. This paper designs and realizes multiple system the PPP and the PPP/SINS integrated navigation algorithm, and the algorithm was applied to IGS stations data and vehicle-mounted high-dynamic of data. Therefore, the main content of the paper as follows:(1) To study the SINS in the local geographical coordinates of the inertial navigation algorithm, SINS of several common coordinate system ,and the exchange relationship between the several kinds of coordinate system;(2) Relevant theories of multi-system PPP algorithm were studied,this paper introduces the basic principle of precise point positioning (PPP),several kinds of commonly used the PPP model, using the kalman filtering method for calculating PPP. By analysis of the data on the IGS station and the actual vehicle-mounted data PPP algorithm can be use, and the results of the data analysis are obtained: Static system PPP positioning accuracy can reach more levels cm or mm, and multiple system than single GPS PPP has higher reliability, and speed up the convergence of PPP; Using high dynamic vehicle data for dynamic PPP, the calculating results with IE8.6 precision.(3) The research of the PPP/SINS composite navigation algorithm is studied, and the basic principle of loose and tightly integrated is introduced. The filter model of the PPP/SINS tightly integrated is deduced in detail, and the PPP/SINS combination algorithm is implemented through the program. With the PPP calculating the same set of on-board measurement data, and the PPP/SINS tightly integrated computation results comparing with IE8.6, come to a conclusion: PPP/SINS IE8.6 precision and its calculating results demonstrate the validity of the algorithm, and combination accuracy is improved obviously, the statistical indicators are better than the PPP, the output information such as speed and at the same time, with a broader needs.