A 1.2 Gbit/s optical transmission system operating at 1550 nm over 67 km of installed dispersion shifted fibre

Results are presented from the first reported 1.2 Gb/s transmission system trial operating with a 1550 nm multilongitudinal mode laser over 67 km of installed dispersion shifted fibre. Temperature tuning the laser allowed measurement of system penalties arising from mode partition noise, giving operational limits for laser/fibre wavelength matching. It is shown that using multilongitudinal mode lasers with a linewidth of approximately=5 nm, the centre wavelength must be matched to within approximately=2 nm of the fibre dispersion zero to maintain an acceptable error performance.<
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