Bistatic SAR image formation algorithm using keystone transform

The ideal solution for bistatic SAR image formation is a two-dimensional matched filtering process. However, this method is computationally intensive due to the range cell migration. In this paper, we present an efficient image formation algorithm for bistatic spotlight SAR processing, which makes use of the keystone transform to correct the range cell migration. So that the two-dimensional matched filtering process can be simplified by the two-dimensional Fourier transform operation. The proposed algorithm´s derivative is based on the time-domain signal model which is more accurate than the approximate frequency spectrum expression. Finally, a hybrid spaceborne/airborne numerical simulation is performed to validate the proposed processing procedure.