Phase-Sensitive OTDR With 75-km Single-End Sensing Distance Based on RP-EDF Amplification

This letter reports the idea of extending the sensing distance of phase sensitive optical time-domain reflectometry system based on remotely pumped erbium-doped fiber (EDF) amplification. A segment of EDF is spliced in the middle of the sensing fiber with the pump power injected from the front end to realize power compensation such as a repeater. The 75-km sensing distance under single-end operating scheme and the 10-dB tail-end SNR are demonstrated. Since the method eliminates the necessity of dual-end operation and field power supply, it provides a much more practical and feasible way of realizing long-range perimeter monitoring.