Research on the Feasibility of PPP Technology in Radar Altimeter Calibration

Abstract

In the background of the satellite altimeter calibration, the author has discussed the feasibility of using the GPS buoy to determine the sea surface height with high precision based on precise point positioning (PPP) technology. In this study, a number of IGS (International GNSS service) stations data were processed by two different solving modes: single-day solution and single-epoch solution, which the used SPODS software is a high precision positioning and orbit determination software containing the PPP model developed by Xi’an Institute of Surveying and mapping. Under the two different solving modes, we can obtain a positioning solution by period and by epoch, respectively. In addition to the IGS static data, we also processed the reservoir dynamic data collected by the GPS buoy and compared the solution with the result processed by GAMIT/TRACK which is a high precision kinematic positioning software by differential positioning mode. Finally, we concluded that the PPP single-day solution accuracy of the static data in X, Y, Z direction is within 1 cm, indicating the PPP can accurately obtain precise coordinates under the corresponding reference frame; the single-epoch solution accuracy in X, Y, Z directions are within 3 cm whose the processed data were selected from the IGS stations the dynamic buoy solution accuracy in horizontal direction is consistent with TRACK’s result, and the accuracy in U direction can reach 5 cm which is meeting the accuracy requirements of altimeter calibration.