Distributed Acoustic Sensing (DAS) has become a popular method of observing seismic wavefields: backscattered pulses of light reveal strains or strain rates at any location along a fiber-optic cable. In contrast, a few newer systems transmit light through a cable and collect integrated phase delays over the entire cable, such as the Microwave Frequency Fiber Interferometer (MFFI). These integrated systems can be deployed over significantly longer distances, may be used in conjunction with live telecommunications, and can be significantly cheaper. However, they provide only a single time series representing strain over the entire length of the fiber. This work discusses theoretically how a distributed and integrated system can be quantitatively compared, and we note that the sensitivity depends strongly on points of curvature. Importantly, this work presents the first results of a quantitative, head-to-head comparison of a DAS and the integrated MFFI system using pre-existing telecommunications fibers in Athens, Greece.

中文翻译：

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链接分布式和集成光纤传感

分布式声学传感 (DAS) 已成为观察地震波场的流行方法：光的反向散射脉冲揭示了光纤电缆沿线任何位置的应变或应变率。相比之下，一些较新的系统通过电缆传输光并收集整条电缆上的集成相位延迟，例如微波频率光纤干涉仪 (MFFI)。这些集成系统可以部署在更长的距离上，可以与实时电信结合使用，并且可以显着降低成本。但是，它们仅提供一个时间序列，表示整个光纤长度上的应变。这项工作从理论上讨论了如何定量比较分布式和集成系统，我们注意到灵敏度很大程度上取决于曲率点。重要的，