Abstract

A method for generating range-angle images of a scene using interferometric measurements from a single pair of receivers (i.e., single base line) is described. The concept is based on a generalization of the Van Cittert-Zernike theorem and utilizes relative motion between the receiver pair and the scene combined with frequency diversity to synthesize an aperture in the Fourier domain of the intensity distribution of the scene. The unique aspects of the concept include the use of a sidelooking geometry to achieve a range-angle image similar to that generated by active synthetic aperture radar (SAR) sensors. Other similarities to spotlight-mode SAR are discussed. In particular, an offset of the synthesized aperture from zero spatial frequency is identified and its impact on the resulting image is considered. A sensor implementation using heterodyne receivers is described, and the principle system trade offs are presented.

© 1986 Optical Society of America