Coarray analysis of the wide-band point spread function for active array imaging

Using the concept of the coarray, an expression is derived for the point spread function for wide-band pulse-echo imaging arrays. The performance of imaging arrays under near- and far-range conditions is analyzed, focusing on linear imaging using line arrays. The results are also extended to the case of planar arrays. The results provide a better understanding of the interplay between bandwidth, element locations, weighting of the elements, pulse shape within the bandwidth, and imaging performance. This leads to new insights on array and pulse design. The results are supported through computer simulations. (C) 2001 Elsevier Science B.V. All rights reserved.