机载导航卫星反射信号海面高度测量

This paper studies the measuring model of sea surface height using the airborne GNSS reflectometry, the estimation method of the delay between direct and reflected signals based on point tracking and model fitting, and error calibration. For the problem of high computational complexity of Z-V model fitting, a new fitting model named as 7-β model is proposed used to compute the delay between direct and reflected GNSS signal. In addition, an error calibration method is developed using the looking-up table and weighted averaging to correct the delay bias caused by the sea state. The validation is implemented utilizing the experimental data acquired by CSIC-IEEC in the Baltic Sea on December 3rd, 2015. The results show that the decimeter-level sea surface height can be obtained by using the existing and proposed methods to estimate the delay between direct and reflected GPS L1 and Galileo E1 signals and then using the proposed approach to correct the delay bias caused by the sea state.