Straight line 20 Gbit/s transmission over 617 km of standard singlemode fibre with dispersion compensation

Results are reported of a transmission experiment at 20 Gbit/s through 617 km of standard singlemode fibre using two-channel-WDM, 10 dispersion compensating fibre units and 12 optical inline amplifiers. With 2/sup 31/-1 PRBS the receiver sensitivities were as low as -32.3 dBm (Mach-Zehnder modulator) and -30.6 dBm (electroabsorption modulator). The optical path penalties after 617 km transmission were 0.5 and 1.5 dB, respectively. >