RCEN: A Deep-learning-based Background Noise Suppression Method for DAS-VSP Records

Recently, distributed optical fiber acoustic sensing (DAS) is regarded as a transformative technology in seismic exploration. However, both various complex background noise and weak desired signals significantly limit its practical application. To explore an effective denoising method for the vertical seismic profile (VSP) record received by DAS, we propose an improved residual encoder-decoder deep neural network (RED-Net) enhanced by deep iterative memory block (DMB) and channel aggregation block (CAB), called residual channel aggregation encoder-decoder network (RCEN). Here, DMB uses the weight accumulation theory to improve the feature extraction ability and achieve accurate noise elimination. Meanwhile, CAB, utilizing the multi-channel analysis architecture, enhances the weak signal retention performance. In addition, we leverage both synthetic data obtained by forward modeling and real DAS noise data to construct a sufficient training dataset with high authenticity, thereby meeting the requirement of network training. Both synthetic and field DAS-VSP data processing results demonstrate the advantage of RCEN compared to competing algorithms, including singular value decomposition (SVD), conventional RED-Net and feed-forward Denoising CNN (DnCNN).