Improving Decoupled Spherical Harmonics ESPRIT Using Structured Least Squares

Spherical arrays have been widely used in direction-of-arrival estimation in recent years, and most algorithms in the spherical harmonics domain typically simultaneously obtain the 2-D angles. In this paper, we first use the structured least squares (SLS) to improve the performance of the decoupled spherical harmonics estimation of the signal parameter via rotational invariance technique (D-SHESPRIT) and propose D-SHESPRIT-SLS. Second, we derive the mean square error of the proposed algorithm and compare estimated results with theoretical results. The simulation results demonstrate the satisfactory performance of the proposed method.