Resonance behavior of a dielectric target in a half-space using the CNR (complex natural resonance) method

The primary objective of this research work is to detect and identify a dielectric target buried below a homogeneous half-space from the backscattered time domain signature. It is well known that the transient scattering of electromagnetic waves from a conducting or dielectric target contains information about the resonance behavior of the target itself as quantified by the complex poles or complex natural resonances (CNR) of the target. This paper describes an approach to model the impulse response of a dielectric target in a half-space using a time domain deconvolution technique. A finite difference time domain code is used to calculate the time domain responses. A singular value decomposition algorithm is used to estimate the impulse response of target and a robust algorithm such as matrix pencil of functions (MPOF) algorithm is used to calculate the CNR's of the scatterer. The extracted poles are compared with the poles scattered by the target in free space.