A New Space-Domain Microwave Imaging Approach to Detecting Inhomogeneous Dielectric Objects

A new approach to reconstructing the dielectric characteristics of unknown inhomogeneous dielectric objects is proposed that is based on the moment method. It is developed in the space domain and derived from an integral equation formulation. By using a numerically evaluated Green function for an inhomogeneous basic configuration (detailed in the paper), one can regards just a part of a scene as an investigation domain. The analytical model is discretized by using the moment method, and a regularization procedure is employed to find a pseudosolution to the resulting rectangular ill-conditioned linear system of algebraic equations. Since the heaviest computations can be performed off line, the computer resources required by the approach are limited. Numerical simulations have been performed to assess the effectiveness of the approach in dielectric reconstruction, in particular, to evaluate both the distortions due to the ill-posedness of the inverse-scattering formulation and the effects of Gaussian noise.