A Least-Squares-Based Algorithm for Estimating ATI SAR Interferometric Phase Errors

ATI SAR systems have immense potential for high-resolution, wide-swath measurements of sea surface currents. However, due to the sensitivity of ATI interferometric phase to phase errors, the retrieval of sea surface currents using ATI technology often relies on ground scene calibration. To address this issue, we first review the principles of ATI SAR sea surface current measurement and analyze the sources and characteristics of phase errors. Based on this analysis, we propose a least-squares-based method for estimating and compensating ATI SAR phase errors. This method ensures robust estimation and correction of phase errors by accounting for their distinct distribution characteristics. Finally, we validate the proposed method using data from the PIESAT-1 satellite constellation, demonstrating its effectiveness.