40 Gb/s field test on an installed fiber link with high PMD and investigation of differential group delay impact on the transmission performance

40-Gbit/s OTDM transmission over a field-installed dispersion-compensated 130-km single mode fibre (SMF) link was demonstrated successfully (BER < 10/sup -12/). The impact of high PMD (7.8 ps) in the order of the RZ pulse width (7 ps) was studied in detail.