Pseudorange positioning model considering DCB correction and kinematic performance evaluation.

In order to evaluate the performance of maritime single point positioning (SPP) performance, taking into account the fact that the broadcast satellite clock correction corresponds to the ionosphere-free (IF) combination or single-frequency B3, a multi-system single-frequency and dual-frequency IF SPP model is derived. The IF and single-frequency SPP positioning accuracy of GPS, GPS/Galileo, GPS/BDS and GPS/Galileo/BDS were evaluated using a set of offshore multi-system GNSS data measured by the unmanned surface vehicle (USV). The results show that compared with the GPS-only system, the SPP positioning performance after the system combination is improved with the plane accuracy of the GPS/Galileo/BDS IF SPP being better than 0.5 m, and the vertical direction accuracy being better than 0.6 m. Compared with the single-frequency SPP, the IF SPP has an improved positioning accuracy of about 1.0 m and 1.3 m in the horizontal and vertical directions, and the IF SPP has better positioning performance.