Novel DAS Extension System Based on Pulse Regeneration

In this work, results from the regeneration of the interferometrie response obtained with a long-range Distributed Acoustic Sensor (DAS) [1] system are presented. These measurements demonstrate the ability of a patent pending prototype of a DAS signal regenerating system which succeeds to restore measurement conditions far away from the low-SNR limit point, improving the range of the system without impairing the performance and capabilities of the DAS set-up. Successive regeneration stages allow the intensity of the probe pulses to be maintained below the Modulation Instability (IM) [2] threshold along the full length of the sensing fiber. Results show how interferometric trace is completely recovered after every regeneration module maintaining this way the quality of the sensing signals throughout the next fiber span. Each of these regenerators contains a detection chain, resulting in a discrete lumped amplification-detection architecture.