Design of a Wideband Probe for the Measurement of the Electrical Parameters of Soil

This paper presents the design of a wideband in-situ probe for measurement of the dielectric properties of soil. A three-dimensional FDTD simulation is used to predict the performance of the probe. The probe uses a circular shaped monopole antenna on a substrate for the transmitting and receiving antennas. The transmitter radiates a differentiated Gaussian pulse that propagates in the soil under investigation. The soil parameters are extracted by mapping the measured S21 parameter (amplitude and phase) to the values obtained from the FDTD simulation. Measuring the soil characteristics in-situ is crucial in applications such as Ground Penetrating Radar (GPR) where interpretation of the radar signal is highly dependent on the ground parameters. However, it should be noted that the designed probe will be used in a sample of landmine free soil, having the same properties of the soil to be tested for landmines with a GPR.