DOA estimation for wideband sources using cross correlation transformation

In this paper, we consider the problem of estimating directions-of-arrival (DOAs) of wideband source signals. A new class of focusing matrices is proposed for use in the coherent signal subspace method. The new method does not require any preprocessing for initial values through using the cross correlation transformation (CCT). Numerical results show that when the DOAs fall within more than one group of one beamwidth each and there are closely spaced sources, the CCT method outperforms the methods requiring preprocessing in terms of root-mean-square error (RMSE).