1 research outputs found
User Demand Based Precoding for G.fast DSL Systems
It can be observed that the achievable rate region of a G.fast DSL system is
no longer rectangular, as it is the case for vectored VDSL systems, due to
stronger crosstalk couplings at high frequencies. Therefore, alternative
operating points that are not optimal in a sum-rate sense may be utilized to
adapt the system performance to the users' actual demands. To this end, we
propose a new precoding scheme based on defining a subset of prioritized users,
where we optimize the sum-rate of the prioritized users under a minimum rate
guarantee for the remaining users. We present a solution based on Lagrangian
duality theory and propose a well-performing one-step heuristic solution. By
means of simulations, we show that significant rate gains for the prioritized
users can be obtained by the proposed precoding scheme