Analysis and Simulation for a Spotlight-Mode Aircraft SAR in Circular Flight Path

A spotlight aircraft SAR in a circular flight path can efficiently obtain an image with very high azimuth resolution or a wider azimuth viewing angle. An analysis on the spotlight SAR is made regarding the required PRF, the predicted resolution, and the computation complexity as a function of the aircraft altitude and the distance between a target and the center of the flight path projection. An efficient processing algorithm based on the exact wide beam spectrum is presented. The results of simulation indicate that the impulse responses meet the predicted resolution performance.