Energy efficient discontinuous operation in vectored G.fast

Intermittent transmission through low power states and discontinuous operation has been introduced in G.fast to enhance energy efficiency. In combination with vectoring, crosstalk cancellation must be maintained on active lines while other lines are in discontinuous operation. Without precautions, the requirements of vectoring may greatly reduce the power saving potential. We describe methods that allow trading off some of the vectoring gain for additional power saving. Using an energy consumption model, we evaluate the energy/rate trade-off of the methods under various traffic profiles. The method called discontinuous vectoring greatly enhances energy efficiency while incurring smaller data rate loss compared to other methods.