Experimental Detection and Characterization of Brillouin Precursor Through Loamy Soil at Microwave Frequencies

This study reports experimental results on detecting Brillouin precursors through loamy-soil dispersive media in the frequency range of 500 MHz to 3 GHz. An experimental technique to collect and analyze the data is presented. Brillouin precursors are shown to be superimposed on the sine-modulated rectangular and Gaussian pulses. The detected Brillouin precursor is shown to have an algebraic amplitude decay behavior through the wet loamy soil considered in this study. Further, a method is proposed to extract the complex dielectric permittivity of the soil from limited experimental data. The experimental results are validated using a theoretical Fast Fourier Transform-based formulation and the experimentally achieved complex dielectric permittivity. These results are also compared with those of using existing theoretical dielectric models. Three different tests are also applied to validate the hypothesis of Brillouin precursor formation.