Digital Beamforming for High Resolution Wide Swath SAR Imaging

Abstract

Multi-aperture SAR-systems allow for digital beamforming on receive that will enable a wide swath SAR with high azimuth resolution. In classic multi-aperture systems, stringent requirements are imposed on sensor velocity and PRF to ensure uniform sampling of the synthetic aperture. This paper shows that an unambiguous reconstruction of the SAR signal is also possi- ble in case of such a non-optimum PRF. For this, an innovative reconstruction algorithm is derived, which enables a recovery of the unambiguous Doppler spectrum also in case of a non-uniform sampling of the synthetic aperture. Further, the influence of perturbations on the reconstruction is presented and general system aspects are discussed.