IMPROVED SPATIAL SMOOTHING TECHNIQUES FOR DOA ESTIMATION OF COHERENT SIGNALS

In the context of coherent signal classification, spatial smoothing is necessary for the application of the eigen-based direction-of-arrival (DOA) estimation methods. However, the currently known spatial smoothing algorithms not only reduce the effective aperture of the array, but also do not consider the cross correlations of the subarray outputs. In this correspondence, an improved spatial smoothing algorithm is presented, which can fully utilize the correlations of the array outputs and produce a more stable estimate of the covariance matrix. Simulation results are provided to verify the theoretical prediction.