Performance Analysis for Two Parameter Estimation Methods of GTD Model

There are two kinds of parameters estimation methods for the Geometrical Theory of Diffraction(GTD) model. One considers the type parameters of scattering center as discrete value, which is extracted before estimating the other parameters. The other considers the type parameters as continuous value and extracts it along with other parameters, then approximates the extracted type parameters as discrete value. In this paper, the Cramer-Ran bounds of two parameter estimation methods are derived respectively, and the estimation performances of these two methods are compared. The conclusions are verified by simulations.