Robust generalised Capon algorithm for estimating the angular parameters of multiple incoherently distributed sources

The authors consider the problem of estimating the directions-of-arrival (DOAs) and angular spreads of incoherently distributed sources, using a uniform linear array. The proposed method is based on the generalised Capon principle and enables the estimation of the DOAs decoupled from that of the angular spreads of sources. Compared with the original generalised Capon algorithm, the proposed algorithm improves the robustness to the mismodelling of the spatial distribution of sources. In fact, this method does not need the a priori knowledge of the azimuthal power distribution of sources, at least for the most studied distributions in the literature which are the uniform distribution and the Gaussian distribution. Furthermore, it works even in the case where the different sources have different angular distribution shapes.