THE OTDR TECHNIQUE AS A PROMISING APPROACH FOR DISTRIBUTED MEASUREMENTS IN OPTICAL FIBRES

摘要

In this paper, we start with a theoretical introduction reminding the basics of the method, the link between the Mode Field Diameter (MFD) and the determination of cut-off wavelength (λ_(co)) and Chromatic Dispersion (CD). Marcuse and Anderson approaches for CD determination are theoretically and experimentally evaluated and compared. We use how a multi-wavelength but standard OTDR (three wavelengths) and a calibrated fibre artefact can be used to derive MFD and then CD. Measurements are performed at 1.31, 1.55 and 1.63μm on links composed of standard single-mode fibres (matched- and depressed-cladding fibres). All these results are achieved through an investigation on measurement uncertainty sources and their impact. This study shows how OTDR noise and linearity as well as an accurate knowledge of the reference fibres influence the accuracy of such a technique.