Centralised optical monitoring of tree-structured passive optical networks using a raman-assisted OTDR

Abstract

Monitoring of tree-structured Passive Optical Networks from a central office is difficult to achieve using a standard OTDR. Switchable reflective elements placed at the ONU can help to discriminate between the branches. In parallel, a Raman assisted OTDR is shown to increase the dynamic range of the reflectometry measurement, thus enabling to detect more faults in the network, and especially fibre breaks after the splitter. ©2007 IEEE.