Efficient Estimation of a Narrow-Band Polynomial Phase Signal Impinging on a Sensor Array

The parameters of interest of a polynomial phase signal observed by a sensor array include the direction of arrival and the polynomial coefficients. The direct maximum likelihood estimation of these parameters requires a nonlinear multidimensional search. In this paper, we present a two-step estimation approach. The estimation requires only a one-dimensional search in the direction of arrival space and involves a simple least squares solution for the polynomial coefficients. The efficiency of the estimates is corroborated by Monte Carlo simulations.