Statistical performance analysis of the minimum-norm method

The authors analyze the performance of the minimum-norm method for estimating the direction of arrival (DOA) of plane waves in white noise in the case of a linear equispaced sensor array. They examine the perturbation in the roots of the polynomial formed in the intermediate step of the minimum-norm method. In particular, asymptotic results for the mean-squared error in the estimates of the direction of arrival are derived. Simple closed-form expressions are obtained for the one- and two-source case to get further insight. Computer simulation results that substantiate the analysis are provided and compared to those obtained for Root-MUSIC. It is shown that the relative performance of the two methods is directly dependent on the ratio of their parameter sensitivities