Algebraic path-following algorithm for localising 3-D near-field sources in uniform circular array

A computationally efficient algorithm is presented for 3-D near-field source localisation using a uniform circular array. Algebraic relations are demonstrated between the incident angles (elevation angle and azimuth angle) under the far-field assumption and the actual near-field location (range, elevation angle, and azimuth angle). Using these relations as paths to follow to the peak of the 3-D MUSIC spectrum, the proposed algorithm replaces the 3-D search required in the conventional 3-D MUSIC with a 1-D path-following after a 2-D initialisation, thereby reducing the computational burden.