Enhanced Backscatter Fibers for Sensing in Telecom Networks

We discuss the application of enhanced backscattering fiber in telecom networks. Such fibers can greatly increase the potential of telecom networks to be used as sensors of network health and its surrounding environment. We describe the effects of increased attenuation and multipath interference (MPI) observed in such fibers as the fiber length and backscattering enhancement increases. For MPI we apply both a well known, approximate three bounce treatment as well as a full solution using coupled mode equations, and we verify the validity of the approximate solution. Our analysis allows us to obtain a sensor reach as a function of the backscattering enhancement level and apply this to interrogation schemes for which the minimum required signal power level and the maximum allowable MPI noise level are known. To show that the backscattering enhancement in our fiber does not interfere with telecom signals, we measure the penalty for signals propagating within and near the enhancement bandwidth in a 10 km length of continuously enhanced backscattering fiber. We find that signals only a few nm away from the enhancement bandwidth can propagate without OSNR penalty.

Automated summary

We discuss the application and effects of enhanced backscattering fiber in telecom networks, including increased attenuation and multipath interference. Our analysis allows us to determine the sensor reach based on the level of backscattering enhancement, and we measure the penalty for signals near the enhancement bandwidth to show that it does not interfere with telecom signals.