The noise and crosstalk environment for ADSL and VDSL systems

This article provides an overview of the noise and, in particular, the crosstalk environment in which DSL technology needs to operate. Transmission on the copper access network is subject to impairments which limit the achievable information capacity, and there is an urgent need to ensure that all DSL systems are spectrally compatible if the capacity of the network is to be fully realized. This article discusses the principles of frequency planning in copper access networks that help to ensure compatibility of deployed systems.