Loss Effects on Time-Reversal Imaging: Analytical, Numerical, and Experimental Investigations

In this article, the impact of lossy media on the time-reversal (TR) imaging procedure in the context of source inverse problems has been investigated by employing an electric field integral equation (EFIE) formulation. Unlike in lossless scenarios where the TR imaging procedure yields the main image accompanied by its ghost images, it is revealed that lossy media introduce additional spurious images. To tackle this challenge, we propose three methods. The effectiveness of the proposed methods is examined by applying them to the challenging problem of locating partial discharges occurring in the lossy medium of a power transformer. Utilizing an accurate model of an actual transformer, we conduct comprehensive numerical experiments that corroborate the accuracy and efficiency of the proposed algorithm. Moreover, experimental data were used to further vindicate the algorithm.