Comparison of the direction of arrival estimator for a circular aperture with triangular and square configurations

The trade-offs between using an antenna with a circular aperture with phase centers in an isosceles triangular configuration versus a square configuration are examined for a semi-active seeker application. Estimators for azimuth and elevation angles were derived using small angle approximations and by minimizing the squared error. The variance and unambiguous angle of the estimators are determined. The theoretical and simulated results indicate that the error in the angular estimates for the triangular configuration is slightly smaller than the square configuration.