Preliminary Research on Nonlinear Correlation Coefficient Criterion in EMTR Method for Spatial Radiation Source Localization

To enhance the precision and resolution of radiation source localization using electromagnetic time reversal technology in free-space environments, this paper introduces a novel nonlinear correlation coefficient criterion that employs the Gaussian kernel function. A series of simulations were conducted to evaluate the effectiveness of this new criterion against the conventional energy criterion and the linear correlation coefficient criterion. The simulation results reveal that the Gaussian kernel-based nonlinear correlation coefficient significantly reduces the size of the focusing spot within the localization region, thereby boosting spatial resolution. Moreover, the application of the nonlinear correlation process effectively eliminates the pseudo-focusing spot adjacent to the radiation source, leading to a prominent improvement in spatial localization resolution.