A new fast Back-Projection Algorithm using Polar Format Algorithm

By dividing subapertures, accumulating signal coherently stage by stage in polar format coordinate, Fast Factorized BPA (FFBPA) avoids the progress in Back-Projection Algorithm (BPA) of repeatedly searching every signal in full aperture for every pixel. Thus the amount of computation is remarkably reduced. Theoretically, the more stages it takes, the less time it´ll cost. However, the error coming along with the interpolations also terribly accumulates. The more stages it takes, the more error will be brought in. To solve this paradox, combining with the original Polar Format Algorithm (PFA), a new Fast BPA is proposed in this paper. Analysis and simulations indicate that our algorithm is more efficient than FFBPA.