A Robust Time-domain Algorithm for Multichannel HRWS SAR Imaging

Abstract:
Azimuth multichannel (AMC) synthetic aperture radar (SAR) system via digital beam forming (DBF) processing is capable of realizing high-resolution and wide-swath (HRWS) focusing, which presents huge potentials for Earth observation. A robust minimum-entropy-based weighted back-projection algorithm (ME-WBPA), a time-domain algorithm, is developed to obtain high-quality images for AMC HRWS SAR in this paper. Considering phase mismatches among receiving channels, the signal model in SAR complex-imagery domain is first established. Then, channel phase biases can be estimated and calibrated according to minimum entropy criterion. Validation of the proposed approach is demonstrated with the real measured airborne AMC SAR data.