Interpolation can also be avoided in the reconstruction if Chirp z-transform (CZT) is used to perform the two consecutive linear mappings.
[21.] Lanari, R., "A new method for the compensation of the SAR range cell migration based on the chirp z-transform," IEEE Transactions on Geoscience and Remote Sensing, Vol.
Therefore, the product vector z can be efficiently evaluated by performing the Chirp Z-Transform
(CZT) [29, 30] on the discrete function dm(n), for each m, m = 0,1,..., M - 1, hence the computation complexity to evaluate z is O (MN [log.sub.2] 2L).