Sensitivity analysis of electrically small objects in lossy inhomogeneous structures

Accurate response Jacobians can significantly improve the convergence and the resolution of the reconstruction algorithms used in inverse microwave imaging. As the electrical size of an object decreases, however, the accuracy of the computed Jacobians with respect to its shape and constitutive parameters deteriorates. This is especially valid if finite-difference (FD) approximations are used. In this paper, we investigate the accuracy of the …