REDUCED-COMPLEXITY DIRECTION-OF-ARRIVAL ESTIMATION FOR LARGE-APERTURE ANTENNA ARRAYS EMPLOYING SPATIAL AMBIGUITIES

Recently, there has been increased interest in using spatially-aliased antenna arrays for direction-finding, whereby the ambiguities associated with the identified angles are resolved using either additional hardware (e.g. sub-arrays) and/or additional numerical processing. In this paper, we describe a direction-of-arrival estimation technique for large-aperture uniform linear arrays whose inter-element spacing causes ambiguities in the measured DOAs. The method assumes knowledge of the frequency of transmission and employs a limited-range MUSIC search of source angles, from which the ambiguous source directions are then identified due to the array's structure. These angles are then used to generate test statistics employing a limited set of time-domain correlation values for pairs of element signals from the array, whereby the maximum of the test statistic corresponds to the true angle of arrival. Numerical evaluations show the viability of the method.