Failure location mechanism in long-reach PON based on OCDR

An efficient and unambiguous failure monitoring and protection mechanism is proposed in long-reach passive optical network (LR-PON). Optical code domain reflectometer by optical coding scheme is utilized. Improved optical encoders are placed centrally in optical distribution network and at both sides of each remote node to monitor all links and nodes in the network, which can make much simpler installation and smaller management costs. A reliable and robust protection system is designed and it can protect LR-PON from multiple fault cases. The network can achieve monitoring and protection process by network management system centrally. After locating fault, the system can also monitor the network continuously. The performance analysis of the monitoring system: signal-to-noise-plus-interference ratio, signal-to-interference-ratio and signal-to-noise-ratio are studied. Furthermore, the performance of data signals for protection system is investigated by bit error rate. The results obtained prove the feasibility and efficiency of the proposed network, and it can support high network capacity.