Inversion of guided waves in georadar data

We analyze the dispersive characteristics of the electromagnetic guided waves (at georadar frequency) to infer the electrical properties of materials that constitute a layered wave guide. WARR (Wide Angle Reflection and Refraction) georadar acquisitions could be carried out in both TE (Transverse Electric) and TM (Transverse Magnetic) configuration to collect the full wavefield at different offset from the source. The dispersive curves of TE and TM modes are obtained by transforming the space-time acquisition into phase velocity-frequency domain (f-v spectrum); the relative maxima in the fv spectrum represents the different propagation modes. We adopt both global and local inversion algorithms for minimizing the misfit function between measured and theoretical curves in order to obtain a ID model of the layered subsoil (thicknesses and electrical permittivity).