IMAGE CHARACTERISTICS IN APPLICATIONS UTILIZING DILUTE SUBAPERTURE

When a large aperture is synthesized with an array of smaller subapert ures for high-resolution imaging applications, it is important not onl y to arrange the subapertures to achieve minimal spatial frequency red undancy but also to choose the size of the subapertures (i.e., the dil ution ratio) necessary to achieve the best possible image quality. Spu rious or ghost images often occur even for nonredundant dilute subaper ture arrays. We show that array configurations producing a uniform mod ulation transfer function will not exhibit these undesirable ghost ima ges. A prescription that is unique and original (to the best of our kn owledge) is then presented for constructing both one-dimensional and t wo-dimensional configurations of dilute subaperture arrays that result s in a uniform spatial frequency response with an arbitrarily high spa tial resolution for reciprocal path-imaging applications.