Matlab-based finite difference frequency-domain method for microwave breast imaging

• Online Access: http://hdl.handle.net/2047/d10008767

The FDFD electromagnetic model computes wave scattering by directly discretizing 's equations along with specifying the material characteristics in the scattering volume. No boundary conditions are need except for the outer grid termination absorbing boundary. We use a sparse matrix Matlab code with loose generalized minimum residue (LGMRES) Krylov subspace iterative method to solve the large sparse matrix equation, along with the Perfectly Matched Layer (PML) absorbing boundary condition. The PML conductivity profile employs the empirical optimal value from[1-2]. This method is easily manipulated and general-geometry oriented, it is fast comparing to other models for solving the whole 3D computational grids. The inverse scheme based on the forward FDFD model is also investigated. A novel matrix-based Born approximation is used instead of the traditional integral Born approximation. Tikhnov Regularization is employed. The good results have been obtained based on the simulated data from 2D FDFD TM model.