Novel algorithm for real time imaging of objects in a half-space with unknown characteristics

In this paper a novel auto-focusing approach has been proposed to the reconstruction of dielectric objects in a lossy earth with unknown characteristics. The fast Fourier transform has been used to cut down the computing time. An exponential refocusing time factor has been introduced. The rule to choose the optimal focusing time is determined by the minimum entropy criterion. Numerical results have shown that the proposed algorithm can provide a good location of the embedded objects in a short computing time despite the inaccurate estimation of earth electrical parameters.