A Lightweight Network Model Based on an Attention Mechanism for Ship-Radiated Noise Classification

Recently, deep learning has been widely used in ship-radiated noise classification. To improve classification efficiency, avoiding high computational costs is an important research direction in ship-radiated noise classification. We propose a lightweight squeeze and excitation residual network 10 (LW-SEResNet10). In ablation experiments of LW-SEResNet10, the use of ResNet10 instead of ResNet18 reduced 56.1% of parameters, while the accuracy is equivalent to ResNet18. The improved accuracy indicates that the ReLU6 enhanced the model stability, and an attention mechanism captured the channel dependence. The ReLU6 activation function does not introduce additional parameters, and the number of parameters introduced by the attention mechanism accounts for 0.2 parts per thousand of the model parameters. The 3D dynamic MFCC feature performs better than MFCC, Mel-spectrogram, 3D dynamic Mel-spectrogram, and CQT. Moreover, the LW-SEResNet10 model is also compared with ResNet and two classic lightweight models. The experimental results show that the proposed model achieves higher classification accuracy and is lightweight in terms of not only the model parameters, but also the time consumption. LW-SEResNet10 also outperforms the state-of-the-art model CRNN-9 by 3.1% and ResNet by 3.4% and has the same accuracy as AudioSet pretrained STM, which achieves the trade-off between accuracy and model efficiency.