关键词: 水下无人航行器, 自干扰抑制, 阵列信号处理, 被动声纳

Abstract: The underwater unmanned vehicle (UUV), as an intelligent underwater operational system, generates self-noise during operation that can significantly interfere with the side-array sonar. The current mainstream adaptive beamforming techniques are primarily designed to suppress far-field interference and exhibit insufficient adaptability for addressing UUV self-interference, which is a type of strong near-field interference. To address this issue, this study proposes a UUV self-interference suppression algorithm based on covariance matrix reconstruction. Given the rigid connection between the side array and the UUV, the covariance matrix of the UUV self-interference exhibits high temporal stability under constant operating conditions. Leveraging this characteristic, the algorithm first estimates the self-interference covariance matrix using pre-collected data, and then utilizes this matrix to modify the covariance matrix of far-field interference and noise. Consequently, an interference-plus-noise covariance matrix is constructed to compute the weights of the adaptive beamformer. Experimental results indicate that, compared to current mainstream adaptive beamforming methods, this algorithm performs better when the input signal-to-noise ratio exceeds 0 dB. Moreover, compared to matrix filtering methods, this approach can enhance interference suppression by approximately 6 dB.

Key words: unmanned underwater vehicle, self-interference suppression, array signal processing, passive sonar