Research On The Method Of Ocean Altimetry Measurement Based On Beidou Satellite Reflected Signals

At present, BeiDou reflected signals are widely used on ocean altimetry measurement, ocean wind and wave retrieve, ice detection and soil moisture detection etc. The angles of BeiDou GEO satellites change little relative to the ground, which can provide stable geometric relationship At the same time, BeiDou GEO satellites have a good ability to cover the low and middle latitude area. So they can improve the ocean altimetry measurement accuracy of the coastal waters, enhance the early warning capability to the bad marine weather, service the marine disaster prevention and mitigation, which is significant.In this paper, the method of ocean altimetry measurement based on BeiDou satellite reflected signal is explored and studied, which mainly includes the following aspects:Firstly, the conditions of ignoring the earth curvature effect in the process of ocean altimetry measurement using BeiDou satellite reflected signals is deduced, which simplifies the altimetry geometry relationship. Through the analysis of satellite movement model and ocean scattering delay model, the corresponding altimetry model using BeiDou satellite reflected signals is constructed, and the error sources affecting altimetry model are analyzed, the ways of reducing the error is found.Secondly, research on the method of receiving and processing the weak BeiDou satellite signals. The altimetry measurement method using related power frontier point for mutation code phase delay can improve the precision of measurement is proved. And the different influencing factors of the accuracy of the measurement are analyzed. In the Matlab simulation environment, the progressing program of direct signals acquisition and tracking algorithm, reflected signals correlation processing method and ocean altimetry retrieve algorithm are developed. In addition, which are verified by the actual data.Finaly, after completing the research of ocean altimetry measurement model and the altimetry measurement method of code phase, the ocean altimetry measurement software system is designed and implemented with C++ language in the Visual Studio 2008 environment. And the testing platform is established, collecting and processing the experimental data. And the usability and stability of the software system is verified.