A Focus Stacking Algorithm for Airborne SAR Images

An image formation processing of airborne synthetic aperture radar (SAR) assumes a focal plane for motion compensation (MoCo). When a focal plane is set on the ground, top of a high building might be blurred in the resulting SAR image. Therefore, we propose a focus stacking algorithm to make a focused airborne SAR image. This algorithm automatically combines some subdivided SAR images which have different focal planes each other. Autocorrelation is calculated at each pixel as azimuth focusing reference index to find the most focused image. It needs no external information such as digital surface model (DSM).