Unitary root-MUSIC with a real-valued eigendecomposition: A theoretical and experimental performance study

A real-valued (unitary) formulation of the popular root-MUSIC direction-of- arrival (DOA) estimation technique is considered. This Unitary root-MUSIC a lgorithm reduces the computational complexity in the eigenanalysis stage of root-MUSIC because it exploits the eigendecomposition of a real-valued cov ariance matrix, The asymptotic performance of Unitary root-MUSIC is analyze d and compared with that of conventional root-MUSIC. The results of this co mparison show identical asymptotic properties of both algorithms in the cas e of uncorrelated sources and a better performance of Unitary root-MUSIC in scenarios with partially correlated or fully coherent sources. Additionall y, our simulations and the results of sonar and ultrasonic real data proces sing demonstrate an improved threshold performance of Unitary root-MUSIC re lative to conventional root-MUSIC. It can be then recommended that, as a ru le, the Unitary root-MUSIC technique should be preferred by the user to the conventional root-MUSIC algorithm.