Fast imaging algorithm for the multiple receiver synthetic aperture sonars

Abstract

For the multiple receiver synthetic aperture sonar, traditional fast imaging algorithms are limited by the approximation of the point target reference spectrum (PTRS). To solve this problem, a novel imaging algorithm based on a new PTRS is proposed in this study. With the presented method, the matched filtering function in the azimuth dimension must be first derived. Then, the range–azimuth coupling phase is obtained by using the difference between the PTRS and the matched filtering function in the azimuth dimension. To perform the decoupling between the range dimension and the azimuth dimension, the bulk range cell migration correction (RCMC) and the differential RCMC based on the range-dependent sub-block processing method are used. Compared to traditional methods, the new method avoids the complicated series expansion. Furthermore, it can handle the general case with the explicit point of the stationary phase. Processing results of the simulated data and the real data indicate that the high-performance results can be got by using the presented method. Moreover, it further shows that the presented method is very suitable for the wide-swath imagery.