Spotlight SAR processor by using extended frequency scaling

Frequency scaling algorithm (FSA) is generally used as a spotlight synthetic aperture radar (SAR) processor. FSA can directly process dechirped raw data. However, the plain algorithm itself is purposed for a single target because the formula of the algorithm is for a target. This paper presents a method to process a sliding spotlighted scene with FSA. Extended frequency scaling algorithm (EFSA) is used for focusing a point target in this paper. In order to get a focused scene of high quality image, effective velocity and Doppler centroid need to be very accurate for each target. Test has been done with a step steering sliding spotlight simulated raw data.