Enhanced Azimuth Resolution in Synthetic Aperture Radar Using the MUSIC Algorithm

This paper addresses a considerable improvement of azimuth resolution in the stripmap mode of synthetic aperture radar (SAR) using the multiple-signal classification (MUSIC) algorithm. At first, the range compression and range migration correction are performed. Azimuth chirp signals of stationary targets will be resolved by conventional azimuth compression operation if the signals have slow-time separation larger than the reciprocal of their frequency bandwidth. Otherwise, they will be merged together and appear as a single stationary target in the SAR imaging. The scenario of close targets is modelled as a multipath problem and the corresponding time-delays are estimated using the super-resolution MUSIC algorithm. Therefore, stationary targets with close centers, which were merged by conventional azimuth compression operation, will be resolved and the azimuth resolution is considerably improved. Numerical results are presented to validate the theoretical discussions.