VDSL MODEM DIVIDED INTO A DIGITAL AND AN ANALOG PART

摘要

The invention relates to a new type of VDSL-modems where the VDSL-modem is divided into on one hand an analog part which is placed in the optical node, and on the other a digital part which is placed in the local station. The analog part of the VDSL-modem consists of A/D-converter and D/A-converter, filter, amplifier, hybrid/balun, adaptive noise attenuator, optical interface and possibly echo canceller. The digital part of the modem consists of an FFT/IFFT-processor, a synchronizer, an equalizer, an interleaving unit, an error correction unit, a protocol manager, and an optical interface. The invention simplifies i.a. synchronization of the modems and reduces the power consumption in the optical node. The multiplexor function in the optical node in addition will be simpler because it need not manage a protocol.