Temporal smoothing for subspace tracking of multipath signals in fading channel

This paper presents an approach based on a preprocessing technique that allows the conventional subspace tracking method to be adapted to the case of coherent or highly correlated multipath signals in fading channels. The preprocessing technique, known as temporal smoothing, makes use of the independent fading property of the signal paths to decorrelate them. It gives better resolution than the common spatial smoothing methods in tracking the directions of the coherent paths.