Inverse Electromagnetic Imaging via Time-Reversal Method of Moments

The electromagnetic sensing and imaging has many potential important applications such as localization and identification. Advanced methods need to be developed for fast and accurate electromagnetic image reconstruction, especially when the received electromagnetic signals are corrupted by a large amount of noise and interference. Here we propose such advanced method to tackle this problem through combination of the electromagnetic time reversal method and the Method of Moments (MoM), with the help of reciprocity theorem. First, electromagnetic time reversal method in the frequency domain is used to obtain the approximate electromagnetic image; then the reduced estimated image domain is obtained by thresholding the intensity of the roughly reconstruct image; finally, with the help of electromagnetic reciprocity theorem, the MoM is applied to the reduced image domain to reconstruct the electromagnetic image efficiently. Simulations have been performed for an electromagnetic sensing and imaging metallic cube system with 3 radiating dipole antennas and 28 receiving antennas aligned in the vertical direction to validate our proposed method, and the results are very promising.