Subarea Approach for Curvature Error Compensation in Spotlight SAR Imaigng Using PFA Interpolation

In SAR imaging, when the range from a platform to a target is not large enough compared to the target scene diameter, the curvature error in the mixing process can be significant and it distorts an image. In order to reduce the effect of the curvature error on the image, subarea technique is utilized when the far-field assumption is invalid. We propose the subarea technique that reduce the curvature error by reducing the size of the target area while reducing the discontinuity at the same time.