An alternative approach to generalized ESPRIT with a better performance

In this paper, azimuth directions-of-arrival (DOAs) are estimated from an arbitrary array without the requirement of entire array geometry information. Impinging directions are estimated by only exploiting the corresponding displacements between the different subarrays. The performance of generalized ESPRIT is improved by including the orthogonal property of signal and noise subspaces, and alternate projection of estimated signal subspaces. Both modified search-based and search-free methods are presented and simulation results are also provided for closely spaced signal sources.