130-km-sensing-range Single-ended High-sensitive Distributed Acoustic Sensor based on Phase-senstive OTDR assisted by Remote Optically Pumped Amplifier

In this Letter, we report a high-sensitive singleended distributed acoustic sensor based on a phase-sensitive OTDR with the 130 km operating distancealong standard single mode telecom fiber. This sensing range is achieved by incorporating a single erbium-doped fiber segment and remotely pumping it using same sensing fiber at a distance of 98 km from the near end.