This paper deals with magnetic source characterization in time domain. The basic idea is to solve the inverse problem using the measured near field radiation cartography. In order to ensure the identification procedure, the Time Reversal (TR) technique is used. This procedure allows both the spatial and temporal focusing determination by forcing waves to virtually converge to their initial source. The originality of the proposed methodology is to present a full time domain study of a magnetic source reconstruction. Indeed, this approach is particularly suitable for structures that emit non-sinusoidal radiations such as power electronic systems. First, the Electromagnetic Time Reversal (EMTR) basis are introduced. Then a simulation case study is discussed. Finally, results from an experiment test are presented to verify the proposed methodology. The measured results are in good agreement with the calculated electromagnetic fields. The experimental validation shows that compared to other identification techniques, especially those developed in the frequency domain, the proposed approach is more efficient and simple.