Radar imaging of buried objects

Radar detection and identification of buried objects such as landmines relies on the wave scattering characteristics of the object and signal processing techniques. The effects of soil and object parameters on microwave imaging are investigated based on Finite-Difference Time-Domain (FD-TD) simulation and laboratory studies. Range of soil permittivity considered is from 2.6 to 7.6 corresponding to dry soil and a volumetric soil moisture of 16%. Both plastic and metallic objects are imaged. The diameter of the objects considered ranges from 9 cm to 15 cm and their height ranges from 3 cm to 5 cm. The simulation and laboratory measurement results are processed using the conventional inverse synthetic aperture radar (TSAR) imaging. It is found that when an object diameter is larger than a wavelength, its image is discernible and becomes clearer when its diameter exceeds two wavelength. It is also found that a plastic object with a dielectric constant of 3.9 embedded in a dry soil medium with a dielectric constant of 2.6 can generate an image with the correct geometric shape