An Experimental Comparison Between the Born and RYTOV Approximations in Microwave Tissue Imaging

Microwave holography is a direct inversion algorithm that shows promise for use in real-time near-field tissue imaging. However, the methodology depends on the linearization of the scattering problem which, in reality, is nonlinear. Therefore, the choice of the linearization method significantly impacts the reconstruction output of holography. Two linearization strategies, the Born and the Rytov approximations, are explored. To analyze their fidelity, the approximations are applied to a tissue-imaging problem. Results suggest that the Rytov approximation is advantageous in tissue imaging.