Accurate Antenna Characterization for Wideband Synthetic Aperture Radar Processing

The airborne F-SAR sensor, developed and operated by the DLR Microwaves and Radar Institute, provides very high resolution, fully polarimetric synthetic aperture radar (SAR) data in multiple frequency bands that are enhanced by several interferometric imaging modes. The high resolution/high bandwidth regime of operation introduces significant challenges regarding both data calibration and image formation, or focusing. This paper reviews the methods for accurate antenna characterization and the parameter extraction for SAR data processing. The antenna measurements must accurately portray interactions with the surroundings as mounted on the aircraft. The results presented concern the antenna characterization itself and illustrate how the quality of real polarimetric and interferometric SAR data is significantly improved.