Abstract
Conventional direction-of-arrival (DOA) estimation methods generally rely on the white Gaussian noise assumption, making them ineffective in hybrid noise scenarios. This paper proposes a deep neural network based on sparsely-gated mixture-of-experts (SMoE) mechanism for underwater DOA estimation in hybrid noise environments. The model first transforms the complex covariance matrix of the array signal into two real covariance matrices via the method of separating real and complex parts. Subsequently, a CNN is employed to extract spatial features from the array signal. Finally, a SMoE mechanism is utilized to handle hybrid noise environments, which dynamically adapts to diverse noise conditions via sparse expert activation. With our staged training strategy, the model achieves 0.94\(^\circ\) RMSE at 0 dB SNR with six noise types, outperforming conventional approaches. This work provides a feasible solution for DOA estimation in hybrid noise environments.
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Relevant information and codes are available from the corresponding author if required.
Code availability
The custom code used for data processing and analysis in this study has been deposited in the Zenodo repository with the DOI 10.5281/zenodo.18286738.
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Acknowledgements
The research was supported by the Development of Key Data Algorithms for Jizhi Ship Technology (November 2055072401) and 2024 Project of Intelligent Detection System for Sensitive Information in Bastion Host Screen Recordings (Number 2055072409).
Funding
The research was supported by the Development of Key Data Algorithms for Jizhi Ship Technology (Number 2055072401)
and 2024 Project of Intelligent Detection System for Sensitive Information in Bastion Host Screen Recordings (Number 2055072409).
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Conceptualization, W.X. and S.Y.; methodology, S.Y.; investigation, W.X. and H.G.; formal analysis, W.X. and C.W.; writing–original draft, W.X. and Z.Z.; supervision, S.Y. and H.G.; validation, W.X. and S.Y.; funding acquisition, S.Y. All authors have read and agreed to the published version of the manuscript.
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Xu, W., Yi, S., Gu, H. et al. Underwater acoustic vector DOA estimation in hybrid noise environments based on sparsely-gated mixture-of-experts mechanism. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37217-3
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DOI: https://doi.org/10.1038/s41598-026-37217-3


