Ocean surface velocity estimation in multichannel ATI-SAR systems

Conventional along-track interferometric (ATI) synthetic aperture radar (SAR) systems derive the ocean surface velocity from an estimate of the phase difference between the SAR echoes received from two displaced phase centres with a single time-lag. A maximum likelihood algorithm is proposed to process multichannel SAR data from an array of phase centres with multiple time-lags. The new technique provides better estimation accuracy than the conventional technique, unambiguous velocity retrieval, and extended operational capability