Fig. 1. Diagram of the side-scatter lidar

Fig. 2. The side-scatter lidar signal

Fig. 3. The structure of the proposed model

Fig. 4. Residual network structure

Fig. 5. CBAM structure

Fig. 6. Comparison of ReLU and SELU

Fig. 7. Simulation images. (a) Original image; (b) Noised image corresponding to noise model 1; (c) Noised image corresponding to noise model 2; (d) Noised image corresponding to noise model 3

Fig. 8. De-noising images. (a) Wavelet threshold (Soft); (b) Wavelet threshold (Hard); (c) Wiener filtering; (d) VGG16; (e) DnCNN; (f) DnCNN+

Fig. 9. Change of the Neural network loss

Fig. 10. Difference distribution of the signal photon number

Fig. 11. Distribution of the relative error