Aligned Propagator Scanning Approach to DOA Estimation of Circular and Noncircular Wideband Source Signals

The problem addressed in this paper is focused on the direction-of-arrival (DOA) estimation of the circular and noncircular wideband signals. The propagator scanning scheme is applied to the array output augmented cross covariance matrix by aligning first the baseband array observation. When the scanning angle equals a true DOA of signal, the complex envelope of the corresponding signal is perfectly aligned, and then, the associated propagator can be used to fulfill subspace separation based wideband direction finding. This method involves no data focusing and eigendecomposition. The performance of the proposed method is analyzed in terms of the mean-square errors of the DOA estimates. Simulation results are included to evaluate the new technique and to verify the performance analysis.