Optimizing Power Normalization for G.fast Linear Precoder by Linear Programming

Summary, in English

The use of vectoring for crosstalk cancellation in

the new ITU-T G.fast standard for next generation DSL systems

becomes essential for efficient utilization of the extended

bandwidth (up to 200 MHz). In VDSL2 (up to 30 MHz),

a zero-forcing-based linear precoder is used in downstream

which approaches single-line performance. However, at high

frequencies, the linear precoder may amplify the signal power

substantially since the crosstalk channel is much stronger

than at lower frequencies. Performance could be significantly

degraded by power normalization to keep the PSD below the

mask. In this work, we extended a per-line power normalization

scheme by linear programming (LP) optimization. By

simulations using measured cable data it is shown how the LPbased

scheme further improves the linear precoder and it is

also capable of balancing the data rate between lines. Further,

the simulations also show the non-linear Tomlinson-Harashima

precoder performs better than the linear precoders.

• Author: Francisco Müller; Chenguang Lu; Per-Erik Eriksson; Stefan Höst; Aldebaro Klautau
• Department/s: Department of Electrical and Information Technology
• Publishing year: 2014
• Language: English
• Pages: 4060-4065
• Publication/Series: 2014 IEEE International Conference on Communications, ICC 2014
• Links: http://dx.doi.org/10.1109/ICC.2014.6883973
• Document type: Conference paper
• Publisher: IEEE - Institute of Electrical and Electronics Engineers Inc.
• Topic: Electrical Engineering, Electronic Engineering, Information Engineering
• Conference name: IEEE ICC 2014 - Selected Areas in Communications Symposium
• Conference date: 2014-06-10 - 2014-06-14
• Conference place: Sydney, Australia
• Status: Published
• ISBN/ISSN/Other: ISBN: 9781479920037