Higher order direction finding for arbitrary noncircular sources : The NC-2Q-music algorithm

These two last decades, Higher Order (HO) High Resolution (HR) Direction Finding (DF) algorithms, such as 2q-MUSIC (q ≥ 1), exploiting the information contained in the HO circular cumulants of the data, have been developed for non Gaussian sources to overcome some limitations of second order (SO) methods. However, for 2q-th order noncircular sources such as M-PSK sources with M ≤ 2q, strong gains in performance may be obtained by taking into account the information contained in both the 2q-th order circular and noncircular cumulants of the data, giving rise to noncircular 2q-th order DF algorithms. As Noncircular HO DF methods are very scarce, the purpose of this paper is to introduce and to analyze some performance of the NonCircular 2q-MUSIC (NC-2q-MUSIC) method (q ≥ 1), for mixtures of arbitrary sources (2q-th order circular or not), typical of operational contexts.