An improved distributed optical fiber sensor (DOFS) for monitoring long-distance buried oil pipeline leakage and intrusion

An improved DOFS for long-distance buried oil pipeline leakage and third-party intrusion detection is presented. A sensing optical fiber cable is buried beneath the soil running along the pipeline. The optical loss of the fiber is sensitive to the soakage of hydrocarbon fuels and the intrusion. The loss is located based on a complementary correlation optical time domain reflectometer (CC-OTDR), and the intrusion and leakage are identified according to the characteristics of transmitted optical power. Theoretic analysis and simulation experiments showed that the application of CC-OTDR could overcome the shortcomings of the prototype based on OTDR.