Power back-off for multiple target bit rates
1998 (English)Report (Other academic)
This contribution describes a new efficient method to perform power back-off in the upstream of a VDSL-system. The method gives higher data rates than the earlier proposals, i.e., the constant back-off method and the reference length method. One conceptual difference with this new method is that we are not using just one design parameter as with the reference frequency and reference length methods. With this new method all users are assigned a certain service class, a target bit rate. The method then performs the power back-off such that it tries to maximize the bit rate (the system margin) for all the other users. The method tries to create FEXT, at each NT, that has the same spectral shape as the background noise. Between 5% and 20% improvement in bit rates is achieved with this new method when using the FSAN models for cable, crosstalk and background noise. The larger improvements over the other methods appear when non-flat background is present. This is because the PSD of the background noise is included in the model used by method. For thinner wires, like the TP1 wire, the method can give more than 20% higher data rate for almost all users.
Place, publisher, year, edition, pages
1998. , 8 p.
, Technical Report, T1E1.4/98-371
Research subject Signal Processing
IdentifiersURN: urn:nbn:se:ltu:diva-22431Local ID: 2d88d780-e123-11dc-9e29-000ea68e967bOAI: oai:DiVA.org:ltu-22431DiVA: diva2:995480
Godkänd; 1998; Bibliografisk uppgift: Standards Project: T1E1.4 VDSL Plano, Texas Nov 30 – Dec 4, 1998; 20080222 (ysko)2016-09-292016-09-29Bibliographically approved