An Underwater Velocity-Independent DOA Estimation Based on Improved Toeplitz Matrix Reconstruction

Conventional acoustic velocity-independent direction of arrival (DOA) estimation models have limited measurement ranges and low degrees of freedom. This paper proposes an omnidirectional DOA estimation model based on improved Toeplitz matrix reconstruction to address these issues. The proposed method focuses on the Toeplitz matrix reconstruction method for sparse arrays to enhance the degree of freedom of the arrays. The method employs an expanding coprime array with a larger aperture, eliminating the acoustic velocity factor through geometric relationships and constructing a larger-size Toeplitz matrix. In addition, the concept of “low-rank matrix reconstruction” is introduced to fill the vacant terms in the Toeplitz matrix. Finally, the simulation experiments demonstrate the effectiveness of the proposed algorithm in improving the estimation accuracy.