Blind direction of arrival estimation using antenna arrays in multipath communication environment

In previous years many digital array processing techniques have been developed for beamforming directed by direction of arrival (DOA) estimation methods. However, the estimates of DOAs using such existing methods are not satisfactory in a multipath environment. A new DOA estimation algorithm (called SUBMUSIC) is presented, which divides the received wavefronts first into coherent groups and then estimates the DOAs of each coherent group separately with a new modified subspace smoothing technique. Unlike similar existing methods, the SUBMUSIC algorithm can be applied to an arbitrary array form and up to (M-1)² DOAs of direct path and multipath components can be estimated, where M is the number of sensors