Optimal spectrum management with group power constraint for digital subscriber loops

This paper proposes a centralized optimum spectrum management (OSM) technique with group power constraint (GPC), which jointly determines total transmission power and power spectral densities (PSD) of the different lines to control the crosstalks in a fully collaborative manner for digital subscriber lines (DSL) systems. Dual decomposition is employed to develop the algorithm for OSM-GPC. Simulation results for practical DSL systems show that the proposed OSM-GPC can achieve better performance than existing OSM with individual link power constraints. In particular, higher rates can be supported for longer links