Improved 2-D Root MUSIC for Non-Circular Signals

This paper proposes an improved two-dimensional (2-D) root MUSIC algorithm for non-circular sources. The proposed method has many advantages over conventional root MUSIC algorithms. First, it requires no pair matching between the azimuth and elevation angle estimation, whereas conventional 2-D root MUSIC algorithms require an exhaustive pair-matching search. Second, the proposed algorithm shows no estimation failure when the elevation angles are between 70 and 90 degrees, whereas the conventional 2-D root MUSIC algorithms fail. Third, the proposed algorithm can estimate the direction of arrival angles (DOAs) of coherent sources, whereas the conventional 2-D root MUSIC algorithms cannot. Fourth, the algorithm does not require any forward/backward spatial smoothing, whereas the conventional 2-D MUSIC algorithms do. Hence, the proposed algorithm can reduce the computational load significantly and can be applied to faster real-time radar/sonar and commercial wireless systems. In addition to these advantages, the simulation results show that the proposed algorithm outperforms the conventional root MUSIC algorithms by a 7 dB gain in signal-to-noise ratio (SNR) to achieve the same root mean square error (RMSE) performance