Underwater Acoustic Source Direction Finding Technology Based on MVDR Beamforming

To address the challenge of low localization accuracy of underwater acoustic sources in complex marine environments, this paper proposes a direction-of-arrival (DOA) estimation system based on a hydrophone array. The system employs a wavelet threshold denoising algorithm for signal preprocessing, and optimizes the threshold function and processing method using a signal-to-noise ratio (SNR) evaluation approach, significantly improving signal quality. A narrowband signal at the dominant frequency is extracted through frequency domain analysis, and high-resolution direction estimation is achieved using the Minimum Variance Distortionless Response (MVDR) beamforming algorithm. On the hardware side, a 16channel uniform linear hydrophone array and corresponding signal processing circuits are developed, featuring low cost and strong portability. The system is validated through experiments conducted in laboratory water tanks as well as in actual lake and marine environments. Results demonstrate that the system exhibits good directivity, high DOA estimation accuracy, and strong environmental adaptability, making it suitable for practical applications such as ocean monitoring and nearshore acoustic source identification.