Altimetric Algorithm and Errors of Ocean Altimetry Using GNSS Reflection Signals

• Published in: China ocean engineering Vol. 29; no. 6; pp. 933 - 944
• Main Author: 郭金运 王书阳 刘新 王建波 常晓涛
• Format: Journal Article
• Language: English
• Published: Nanjing Chinese Ocean Engineering Society 01.12.2015; Key Laboratory of Surveying and Mapping Technology on lsland and Reef of NASMG,Qingdao 266590,China%College of Geodesy and Geomatics,Shandong University of Science and Technology,Qingdao 266590,China%Key Laboratory of Surveying and Mapping Technology on lsland and Reef of NASMG,Qingdao 266590,China; College of Geodesy and Geomatics,Shandong University of Science and Technology,Qingdao 266590,China; Satellite Surveying and Mapping Application Center of NASMG,Beijing 101300,China
• Subjects: Coastal Sciences; Engineering; Fluid- and Aerodynamics; GNSS; Marine & Freshwater Sciences; Numerical and Computational Physics; Oceanography; Offshore Engineering; Simulation; 全球卫星导航系统; 反射信号; 测高算法; 海平面高度; 海洋表面; 海面高度; 误差方程; GNSS refection technique; error propagation; ocean altimetry; sea surface height; specular reflection point
• ISSN: 0890-5487; 2191-8945
• DOI: 10.1007/s13344-015-0066-3

As a new remote sensing technology, the global navigation satellite system（GNSS） reflection signals can be used to collect the information of ocean surface wind, surface roughness and sea surface height. Ocean altimetry based on GNSS reflection technique is of low cost and it is easy to obtain large amounts of data thanks to the global navigation satellite constellation. We can estimate the sea surface height as well as the position of the specular reflection point. This paper focuses on the study of the algorithm to determine the specular reflection point and altimetry equations to estimate the sea surface height over the reflection region. We derive the error equation of sea surface height based on the error propagation theory. Effects of the Doppler shift and the size of the glistening zone on the altimetry are discussed and analyzed at the same time. Finally, we calculate the sea surface height based on the simulated GNSS data within the whole day and verify the sea surface height errors according to the satellite elevation angles. The results show that the sea surface height can reach the precision of 6 cm for elevation angles of 55° to 90°, and the theoretical error and the calculated error are in good agreement.