DOA estimation of partially polarized signals using conjugate MUSIC

With the developments in radar signal processing, it is more common that the received signals are the combinations of noncircular and circular ones. Some variations of MUSIC and ESPRIT have been developed to cope with the case. One typical method has been discussed in [F. Gao, A. Nallanathan, Y. Wang, “Improved MUSIC Under the Coexistence of Both Circular and Noncircular Sources”, IEEE TRANSACTIONS ON SIGNAL PROCESSING, vol.56, no. 7, pp.3033–3038], where all the sources are completely polarized (CP). In this correspondence, an algorithm named conjugate MUSIC is proposed to estimate the Direction-of-arrival (DOA) of partially polarized (PP) signals. Compared with the conventional MUSIC, the conjugated version improves the estimation accuracy by exploiting the noncircularity. Numerical examples show the effectiveness of the proposed method.