A Novel Parameter Estimation Method of the Quadratic FM Signal in Alpha-stable Distribution Environment

Abstract

This paper takes the Alpha-stable distribution as the noise model and studies the parameter estimation problem of quadratic FM signal in the impulsive noise environment. Since the conventional algorithms degenerate severely in the impulsive noise environment, this paper proposes a novel method of fractional ambiguity function basing on the fractional lower-order statistics (FLOS-FAF). Firstly, the fractional lower order Instantaneous correlation function is proposed and is performed by the fractional Fourier transform (FRFT). Secondly, parameters of quadratic FM signal are jointly estimated by peak searching the FLOS-FAF and dechirping method. Simulation experiments verify that the proposed algorithm can suppress the impulse noise and has good performance when poor SNR condition exists.