Performance analysis of the MUSIC algorithm in direction finding systems

The performance of the MUSIC (Multiple Signal Classification) algorithm in determining the bearing of a single emitter from the signals of an array of sensors is investigated. The causes and cures of ambiguities in bearing estimation, due to array response duplications, are addressed first. The statistical properties of unambiguous bearing estimates are then considered. In particular, expressions for the first two moments of the error in these estimates are presented. These expressions, being more general than those that have appeared in the literature, are not limited to a line array of isotropic elements; hence they include the effects of antenna pattern and array geometry on estimation accuracy. The numerical examples verify the analytical moment expressions