Improving GPR signal modelling for efficient characterization of multi-layered media

We propose a plane wave model (PWM) which is derived based on analytical solution of a full wave model (FWM) applied to ground penetrating radar (GPR) signal propagation in layered media. The computation efficiency of PWM is enormous, and accuracy is comparable to FWMs. In this model, reflections from different interfaces and their higher order terms are expressed separately resulting in infinite number of terms for the forward model computation. The mathematical expression of PWM becomes complicated as the number of layers increases, and higher order reflections are considered for better accuracy of the model. It is observed that by applying suitable time window and limiting order of reflections based on GPR system dynamic range, the PWM expression can be simplified to a great extent. The effectiveness of the proposed method is verified by inverting synthetic data of a three layered (3L) media.