Capon Root-MUSIC-like Direction of Arrival Estimation Based on Real Data

Abstract

In this paper, a new direction-of-arrival (DOA) estimation method based on real data Toeplitz matrix is proposed for coherent narrowband signals with a uniform linear array (ULA). First, we construct the data matrix from a single snapshot in a Toeplitz form whose rank is directly related to the DOA of signals regardless of the degree of correlation/coherency of signals. Secondly, we obtain the real data using proposed unitary transformation method. This transformation method may be applied directly to any data in Toeplitz Hermitian symmetric form, whereas the existing methods require complex operations such as construction of the covariance matrix and forward-backward averaging method. Further, we employ the Capon method in conjunction with Root-MUSIC method to estimate the DOAs. The matrix inversion of real data matrix in the proposed method reduces the complexity by 75% compared to Capon method, which uses complex data operations. Finally, using the simulation results we verify the effectiveness of the proposed algorithm compared with Unitary Root-MUSIC.