Efficient method for estimation of the thicknesses and complex dielectric constant of wall

Accurate estimation of the unknown wall parameters is of great importance in through wall radars (TWR). Time delay only measurement is an efficient method to derive real part of dielectric constant (ε\´) and thickness (d) of wall. However the imaginary part of dielectric constant (ε") in lossy media cannot be obtained by this method. To derive ε" and also loss tangent, we upgrade this method using the amplitude of echoes, in addition to their time delays. Since the loss in the medium does not affect the time delays, ε\´ and d is achieved precisely and using them loss components can be computed. In this paper, permittivity, thickness and loss tangent of a plaster slab is measured using the proposed method.