Improved angular resolution for spatial smoothing techniques
J. Li · IEEE Transactions on Signal Processing · 1992
Spatial smoothing techniques are used to estimate the directions of coherent arrivals. The performance of these techniques deteriorates rapidly as the coherent arrivals become closely spaced. The author examines the resolution performance of the existing forward-only and forward/backward spatial smoothing techniques. It is shown that the resolution for coherent signals can be improved by squaring array covariance matrices before forming smoothed array covariance matrices.>