SAR-based technique for soil permittivity estimation

A conventional synthetic aperture radar (SAR)-based technique for soil permittivity estimation is presented in this contribution. Ground penetrating radar imaging techniques are mainly based on SAR imaging algorithms that take into account the wave velocity in the soil for accurate imaging of buried objects. Reflectometers, datasheets, and indirect observation methods are commonly considered for soil characterization. However, factors such as humidity and temperature may cause some variations in the soil constitutive parameters. This contribution proposes a methodology for in situ characterization of soil permittivity, using the known position of a reference object and the application of conventional SAR imaging to recover the reflectivity image, from which the required information to calculate the complex permittivity can be extracted. Experimental validation in both controlled and realistic scenarios proves the capability of the proposed technique to recover the permittivity of different types of soil and to improve the quality of the Underground-SAR image.