Fast direction-of-arrival estimation with known waveforms and linear operators

An efficient direction-of-arrival (DOA) estimation method for narrowband coherent signals with known waveforms impinging on a uniform linear array is presented. Unlike the maximum likelihood (ML)-based methods such as the WCDEML and parallel decomposition (PADEC) methods, the proposed algorithm is a linear operation-based method. It estimates the DOAs by exploiting the shift invariance property of the array geometry without searching over the parameter space or finding polynomial roots. As a result, the computational complexity of the proposed method is significantly lower than that of the WCDEML and PADEC algorithms. Simulation results are presented to show that the proposed method is at least four times faster than the above two state-of-the-art DOA estimation methods, and performs comparably as well.