Research on AOA estimation methods for arbitrary structured arrays

Direction of arrival (DOA) estimation is a critical area in array signal processing, with angle of arrival (AOA) being its core parameter. AOA estimation was taken as the main research objective to enhance accuracy in arbitrary structured arrays. By analyzing the system models of arbitrary structured arrays in the existing literature, a new subspace approximation iterative algorithm was proposed based on E-subspace theory, combined with the maximum likelihood criterion and Lloyd-like iterative algorithm. Furthermore, to reduce computational complexity and improve angle estimation accuracy, an iterative improvement algorithm based on the MUSIC peak range was proposed in conjunction with the MUSIC algorithm. Finally, simulation results demonstrate the effectiveness of the proposed methods in millimeter-wave channel estimation, showing significant performance improvements compared to the traditional MUSIC algorithm.