CWDM access network and prospects for introduction of full-duplex wavelength channels

Using an access network concept based on single mode fibre (SMF) rings and coarse WDM (CWDM), transmission performance is investigated for a dual-fibre (up/ down-stream) scenario. We show that all 18 CWDM channels can be utilised in fibre rings of up to 20 km, even using standard SMF, and we briefly present an experimental verification. Aiming at cost reduction for fibre deployment, prospects for introducing full duplex wavelength channels are estimated with respect to inevitable Rayleigh backscattering. We show that forward error correction (FEC) can mitigate Rayleigh crosstalk significantly and that full exploitation of the CWDM band is feasible achieving sufficient reach.