Coherent Azimuth Ambiguity Suppression Based on Linear Optimum Filtering of Short Along-Track Baseline SAR Interferograms

We propose a coherent ambiguity suppression algorithm for short-baseline interferometric Synthetic Aperture Radar (SAR) systems with modest ambiguity rejection capabilities, typically suited for companion SAR missions. The algorithm leverages Doppler and resolution dependence of the ambiguity to signal ratio to achieve multilooking and ambiguity suppression by minimizing the mean square error of interferometric phase estimates. Besides relaxing the requirements on short-time stability of interferometric signatures, the suggested approach shows good ambiguity suppression performance and tolerance to phase and amplitude calibration errors.