Journal of Geodesy

GNSS-Reflectometry, altimetry, BDS-3, code-level altimetry, shipborne GNSS-R

Global navigation satellite system-reflectometry (GNSS-R) has great potential to be a novel technique for altimetry, which can be used to derive sea surface heights (SSH). Shipborne altimetry is an important method to measure local SSH with high spatial resolution. In order to test the feasibility of shipborne dual-antenna GNSS-R reflector height retrieval, we developed a GNSS-R receiver system and performed shipborne experiments on a research vessel. In the experiments, direct and reflected GPS/BDS signals were collected using the same setup and processed to estimate the reflector height on the basis of path-delay measurements. A strategy of obtaining the GPS/BDS (openly available) code-level path delay based on 10-ms coherent integration waveforms is adopted. We analyze the relationship between the path delay error and the error of the estimated reflector height, and point out that the error in the path delay will be amplified when the satellite elevation is low. We also performed reflector height retrieval based on BDS-3 signals for the first time. We evaluated precisions of the BDS-R and GPS-R derived reflector heights with 30° and 50° cut-off elevations. The results show the standard deviation of solutions at different cases are around 1.0 meter and precisions are slight better for 50° cut-off angle compared to 30° cut-off angle. In general, the mean values of different cases are close with several centimeter differences for the experiments.

Fan Gao

Article

no

2019-08-01

SCI