Time domain sources identification in the near field: comparison between electromagnetic time reversal and genetic algorithms-based methods

Abstract

This study presents a comparative study between two electromagnetic inverse methods based on electromagnetic time reversal (EMTR) technique and genetic algorithms (GAs) for radiating sources characterisation in the near field (NF). Indeed, frequency-inverse methods reveal insufficiencies in transient radiations study. For instance, it leads to a repetitive process for multiple distinct frequencies. To overcome the frequency method limitations, EM inverse method in time domain (TD) successively based on GA and EMTR technique are implemented using analytical equations governing equivalent dipoles radiations. The performance of the two methods is compared in terms of complexity, accuracy, and calculation time. A TD measurement test bench is given using the NF scanning technique. Experimental results confirm that both methods are efficient and provide adequate equivalent models. Nevertheless, GA-based method depends on simplifying assumptions and thus the convergence is not always guaranteed. Therefore, EMTR-based method is more suitable, particularly for high switching frequencies in electronics systems.