Direction estimation using a two-level nested array with gain–phase error calibration

The direction of arrival of multiple signals arriving on a non-uniform linear nested array in the presence of array errors due to gain and phase perturbations is considered in this paper. An l\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ l $$\end{document}-2 norm minimization is proposed for gain and phase error calibration and the direction of signals is estimated using the spectral search method. The proposed method iteratively minimizes the error and reconstructs the covariance matrix subsequently reducing the effect of the error. The results obtained from simulations illustrate the capability of the proposed method in overcoming the performance deterioration due to errors in a nested array.