Sar Processing Algorithms for Envisat Asar Image Mode and Alternating Polarization Mode in the Kspt Envisat Asar Processor

ABSTRACT: This paper describes the Extended Exact Transfer Function (EETF) algorithm used in the Kongsberg Spacetec (KSPT) ENVISAT ASAR processor, in addition to RADARSAT and ERS SAR processors from KSPT. This processor is required to handle and process data from image mode (IM), alternating polarization (AP) mode and wide swath (WS) mode. IM and AP mode are both processed using the EETF algorithm. To process IM the KSPT ENVISAT ASAR processor uses the EETF as-is, and for AP mode it uses the burst-EETF algorithm for coherent processing of each polarization. This implies that both IM and AP mode products exploits high bandwidth and are phase preserving. The EETF algorithm is used because of its speed, ease of implementation and its ability to produce high quality, phase preserving imagery.