分布式声波传感犞犛犘数据中的光缆耦合噪声局部稀疏优化压制方法

The vertical seismic profile records collected by the distributed acoustic sensing system are affected by many factors, such as the poor coupling between the cable and the wellbore, thus the seismic data will be interfered by the optical cable coupling noise with strong energy. The global sparse optimization method does not consider the time-varying characteristics of the effective seismic signal and the optical cable coupling noise when suppressing the optical cable coupling noise, which affects the noise suppression effect. In this paper, an adaptive suppression method of optical fiber coupling noise based on local sparse optimization is proposed. Firstly, the sparsity of the effective signal and the optical cable coupling noise of each time window length is calculated for each seismic data within a series of time windows with preset length, and then the time window length with the optimal sparsity is selected. Finally, the morphological component analysis method is used to suppress the VSP optical cable coupling noise within the optimal window. The results of both synthetic data example and real data examples show that the proposed method is superior to the global sparse optimization.