Joint Scattering Center Enumeration and Parameter Estimation in GTD Model
Mahdi Ghasemi, Abbas Sheikhi
Abstract
In this article, a novel multistage CLEAN-based method based on generalized likelihood ratio test (GLRT) is proposed for scattering centers' enumeration and their parameter estimation. To analyze the performance of the proposed scattering center enumeration algorithm, the probability density function (pdf) of the GLRT is derived for both the known noise variance case and the unknown noise variance case. In addition, we derived a closed form for the probability of correct enumeration of scattering centers, obtained in the case of the known model parameter. A method to reduce the computational complexity of the proposed algorithm has also been introduced. Despite the conventional methods which are based on the damped exponential models, the proposed method uses the geometrical theory of diffraction (GTD) model whose performance does not degrade as the bandwidth increases. The simulation results show an appropriate performance of this method at low signal-to-noise ratio (SNR) situations.