METHOD FOR QUALIFYING THE EFFECTIVE MODAL BANDWIDTH OF A MULTIMODE FIBER OVER A WIDE WAVELENGTH RANGE FROM A SINGLE WAVELENGTH DMD MEASUREMENT AND METHOD FOR SELECTING A HIGH EFFECTIVE MODAL BANDWIDTH MULTIMODE FIBER FROM A BATCH OF MULTIMODE FIBERS

摘要

The invention relates to a method for qualifying the actual effective modal bandwidth of a multimode optical fiber over a predetermined wavelength range, comprising the steps of: carrying out (30) a Dispersion Modal Delay (DMD) measurement of the multimode optical fiber at a single wavelength to obtain an actual DMD plot; generating (32) at least two distinct modified DMD plots from the actual DMD plot, each modified DMD plot being generated by applying to the recorded traces a temporal delay Δt that increases in absolute values with the radial offset value roffset, each modified DMD plot being associated with a predetermined bandwidth threshold (S1; S2); for each modified DMD plot, computing (33) an effective modal bandwidth as a function of said modified DMD plot and comparing (34) the computed effective modal bandwidth (EMBc1; EMBc2) with the bandwidth threshold value to which the modified DMD plot is associated; (35) qualifying the actual effective modal bandwidth as a function of results from the comparing step.