Soil moisture variability effect on GPR data

In this paper the effect of local variability of soil moisture within the antenna footprint on GPR data is studied. A combination of GprMax3D with GPR full-wave model of Lambot and André (2013) is used for an errorless set of measurements. The GprMax3D simulations are used as real GPR measurements regarding several physical-based configurations. The Greens functions of the simulated data are extracted using calibrations based on GPR full-wave models. The inversion results of horizontal local soil moisture variability focusing on the surface wavelet reflection are compared with the averaged soil moisture values within different antenna footprints which led to the antenna footprint of -9 dB as the best. Finally, the inversion results of the vertical soil moisture variability shows significant effect of shallow soil moisture layering on the GPR-retrieved soil moisture values, which is highly correlated to the antenna height from the ground surface.