Constant Offset Autonomous Spectrum Balancing Using Multiple Reference Lines for VDSL

The use of Lagrange multiplier offsets improves the iterative water-filling algorithm for digital subscriber line systems. We present a technique for generating constant offsets using a virtual network of reference lines. We provide simulation results that show that the achievable performance is very close to that of existing state-of-the-art algorithms, while requiring significantly fewer time-consuming interference measurements and reducing the amount of message passing required.