Dependence of landmine radar signature on aspect angle

Antipersonnel landmines have been indiscriminately used since World War II, and their long-term persistence in the ground creates a barrier to development in a large number of countries and forces people to live in constant fear. There is a growing demand for reliable landmine detection and localisation systems to return affected areas to their normal use. Due to its ability of detecting both metallic and non-metallic objects, ground penetrating radar (GPR) is a meaningful method for detecting landmines that may allow faster and safer operations. Unlike common clutter objects, most landmines can be modelled as multiple layered dielectric cylinders that cause multiple interfering reflections and result in features with a characteristic angular pattern. Due to this, landmines are expected to produce signatures that present some discriminant features that could be used for reducing the GPR false alarm rate. In this study, measurements of three inert landmines have been carried out to study and characterise landmine signatures as a function of polarisation angle and aspect angle.