合成孔径雷达高度计波形重跟踪算法的近岸精度分析

针对近岸区域，基于Sentinel-3A合成孔径雷达观测数据，选取多阈值、ICE1、IceSheet和SAMOSA四种波形重跟踪算法，利用全球范围内27个验潮站海面高数据，分析近岸20 km范围内4种波形重跟踪算法的精度。结果表明，多阈值算法在近岸6 km范围内可保留最多的有效波形，且与验潮站海面高数据具有最高的相关性和最小的均方根误差；SAMOSA算法在离岸距离大于5 km时相对大地水准面稳定性最高，更适用于开阔海域。

Analysis on the Accuracy of Waveform Retracking for the Coastal Synthetic Aperture Radar Altimeter Data

We select four waveform retrackers including SAR multi-threshold, ICE1, IceSheet and SAMOSA, to retrack the Sentinel-3A SAR waveforms in the coastal areas. We then analyze the accuracy of the four retrackers within 20 km offshore by comparison with observations from 27 tide gauges. The results show that the SAR multi-threshold retracker can retain the most valid data, and obtain the highest correlation as well as the smallest root mean square error of difference between the derived sea surface heights and the tide gauge sea levels within 6 km offshore. The SAMOSA retracker has the highest stability related to the geoid beyond 5 km from the shore, which can provide high-precision sea surface height in open ocean.