A Generalized Interpretation and Prediction in Microwave Imaging Involving Frequency and Angular Diversity

Abstract

The Ewald sphere representation for the Fourier space data in the monostatic and bistatic frequency diversity imaging is described. From that representation we prove that the Fourier transform reconstruction method is equivalent to the backprojection method. Prediction of an image obtained by the Fourier transform method can be simplified in two steps: first obtaining the range profile at each aspect, and then graphically back-projecting the range profile of each aspect to the image plane along the directions normal to the bisection line. Accordingly, any object image given specified imaging scheme and spectral and angular windows can be predicted. The monostatic image and the bistatic image can look similar if the angular windows utilized in the two imaging schemes are suitably chosen. However, the monostatic image has better resolution. Numerical results verify our interpretation.