Concept and Results of the DLR Realtime SAR (Synthetic Aperture Radar) Processor,

A Realtime Azimuth Processor was developed for the airborne E-SAR system Experimental Synthetic Aperture Radar of DLR. The processor works with an unfocused compression method. This method greatly simplifies the data processing and is easily implemented by a moving average approach. A SAR image processed by a traditional unfocused processing method has a lower contrast, higher sidelobes and worse resolution than in the focused case. A new algorithm was developed, so that a triangular amplitude weighting could be implemented into the unfocused processing method without additional complications. Images processed in realtime are presented. They show good contrast and strong suppression of the sidelobes. The processor hardware can be implemented with reduced costs in small aircrafts and is suitable for several applications such as the detection of oil pollution over the sea.