Adaptive dispersion equalisation by detecting dispersion fluctuations using PM-AM conversion

A novel adaptive dispersion equalisation technique that detects and equalises dispersion fluctuations in transmission fibre during data transmission is proposed. This technique first detects dispersion fluctuations in the fibre by using the PM-AM conversion effect at a monitoring wavelength, and then tunes the data wavelength to equalise the fluctuation. This technique was tested by conducting a 40 Gbit/s, 8.5 ps pulse transmission experiment over 300 km of dispersion-shifted fibre, and was shown to suppress the sensitivity degradation to below 0.2 dB when the temperature of the fibre was varied between 0 and 40/spl deg/C.