Multi-Channel Azimuth Processing in SAR - Airborne Measured Data Demonstration and Analysis

Abstract

Synthetic Aperture Radar (SAR) is a well-proven imaging technique for remote sensing. However, conventional SAR systems are not capable to fulfil the increasing demands for both improved spatial resolution and wider swath coverage. This inherent limitation can be overcome by multi-channel SAR systems, which gather additional information along the synthetic aperture, thus enabling high-resolution wide-swath (HRWS) imaging. In this context an innovative algorithm, namely the Multi-Channel Reconstruction Algorithm (MCRA), was introduced, which allows for the processing of multi-channel data in azimuth. The presented work demonstrates the potential of this algorithm by its application to airborne measured multi-channel SAR X-band data, which were acquired by DLR’s F-SAR system. In a proof-of-principle, the combination of up to 4 different channels is presented. In this context, the impact of different channel balancing methods on the system performance will be evaluated. Furthermore, a performance analysis of the algorithm will be presented, especially with regard to its capability of suppressing azimuth ambiguities. Finally, the validity of the analytic prediction will be verified with the measured data.