Directions-of-arrival tracking of coherent cyclostationary signals without eigendecomposition

By exploiting the cyclostationarity exhibited by most communication signals, we propose a computationally efficient method for estimating the directions-of-arrival (DOA) of coherent narrowband signals impinging on a uniform linear array without eigendecomposition and spatial smoothing processes. An online implementation of this method is proposed for tracking the DOA of moving signals in a multipath propagation environment. In the proposed algorithm, a combination of the cyclostationarity and a subarray scheme are used to decorrelate the signal coherency and to suppress the noise and interfering signals, while the noise subspace is estimated from the resulting cyclic correlation matrix through a linear operation. As a result, the proposed algorithm has the advantages of computational simplicity and robust detection capability.