Specialty Optical Fibers Handbook

fibers with high RDS and (2) applying Raman amplification in fibers with l

0

too

close to the signals.

The beneficial impact on the DCM properties from reducing Tx fiber disper-

sion is shown in Table 5.2. To illustrate the principles, values are drawn from a

family of commercial slope-matched DCMs intended for precise compensation

applications, on the market at the time of writing [43]. Comparing the 17-ps/nm-

km value for G.652 Tx fiber in the first line of Table 5.2 with the 4.5-ps/nm-km

value for G.655 fiber in the second line shows the impact of reducing the length

of DCF in the module on both loss and PMD. The Tx fiber with RDS 

0:01 nm

1

does