Abstract:Underwater object detection based on sonar images is one of the core tasks of underwater intelligent sensing systems. However, the low resolution of sonar images leads to a lack of object details, low contrast, and strong noise masking the target contours, making it difficult for models to learn stable and discriminative object features. To alleviate these problems, a high-precision sonar image feature extraction network is proposed. This method is based on a single-stage target detection framework. By introducing the lightweight space-to-depth convolution module, lossless downsampling is achieved while significantly reducing network parameter redundancy. The lightweight feature enhancement module is used to enhance low-level features, improving the effectiveness of feature extraction. Finally, the spatial and channel synergistic Attention module is introduced to improve the spatial sensitivity and channel selectivity of feature representation. Experimental results on the sonar common target detection dataset show that the proposed method not only reduces the number of parameters but also achieves higher detection accuracy compared to the counterparts.