Abstract:

The back-projection （BP）algorithm can effectively handle the two-dimensional space-variation in missile-borne forward squint synthetic aperture radar （SAR） imaging without image projection. However, the heavy computation is an obstacle for real-time application. A fast time-domain imaging algorithm is proposed. Under the assumption that the range migration variation can be omitted in a small piece of the scene, the image scene and synthetic aperture are divided. By this procedure, the beam formation is carried out uniformly in the sub-scene, which can improve the efficiency. Meanwhile, the errors introduced by the far field assumption are also discussed. Compared with fast back-projection （FBP） algorithm, the computation load of the proposed algorithm is analysed in detail. Finally, the efficiency of the proposed method is validated by simulation results.