Development of a new DAS sensor for recording full strain components

Although DAS (Distributed Acoustic Sensing) is an excellent technique for acquiring seismic waves that have attracted much attention in recent years, it has the disadvantage of being sensitive only in the direction parallel to the fiber and has not yet been widely put into practical use. Therefore, we proposed a new method for estimating the six components of the strain tensor with high accuracy using DAS, which can be estimated only in limited situations using conventional methods. The effectiveness of the proposed method was evaluated by numerical experiments. By changing various parameters (sampling frequency, incident angle, and source frequency), we showed that the proposed method could reconstruct the six components of the strain tensor with better accuracy than the conventional methods, even when any kinds of waves are incident.