In-service fiber line identification based on high-resolution fiber length measurement

An in-service fiber line identification scheme based on high-resolution fiber line length measurement is proposed and demonstrated for single star, survivable, and passive double star architectures to meet the demands of in-service cable reconstruction. In the proposed scheme, a reference fiber is assigned just after the fiber network has been constructed and differences in length between the constructed fiber lines and the reference fiber are measured by OFDR. The measured values are recorded as identification ranges, which include the measurement errors, as unique values of the actual lines. The OFDR length measurement system can measure a wide range of length differences from 4 cm to 3 km. The lines were successfully identified in all three kinds of architecture by the proposed scheme. The scheme is based on the line length, which is an actual property representing the whole line. Therefore, the line data can be verified simply and effectively, according to the actual information on the line