Host medium transformation of the early-time radar response of a buried dielectric target

This paper addresses the problem of predicting the early-time radar response of a low-metal content landmine buried in a lossy soil given its response in a lossless soil. To make the problem tractable, we consider plane wave scattering from a homogeneous dielectric target embedded in a layered host medium with a global loss model. Using similarity analysis and the Born approximation, a transformation law for the scattered field is derived which relates the early-time target response in the lossy host medium to that in a corresponding lossless host medium. We also present a transformation law for the target impulse response, which follows directly from the transformation for the scattered field. The derived transformation law is tested using early-time responses of a mine-like target obtained from 3D finite-difference time-domain (FDTD) simulations. Based on these tests, the ability of the transformation law to predict changes in the early-time response of a non-metallic landmine as a result of changes in the electromagnetic properties of the host medium is discussed.