VDSL transmission systems

US7050489B1 · kind B1 · utility

Assignee

• STMICROELECTRONICS, INC. · US

Inventors

• Frank Sjöberg · Luleå, SE
• Sarah Wilson · Ponteland, GB
• Rickard Nilsson · Luleå, SE
• Daniel Bengtsson · Luleå, SE
• Mikael Isaksson · Luleå, SE
• Tomas Nordstrom · Luleå, SE
• Per Ödling · Ayacucho, PE
• Gunnar Bahlenberg · Luleå, SE
• Magnus Johansson · Luleå, SE
• Lennart Olsson · Luleå, SE
• Sven-Göran Ökvist · Luleå, SE

Key dates

• Filing date: Nov 18, 1999
• Grant date: May 23, 2006
• Expiry date: Nov 18, 2019

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L5/0007
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

One problem, frequently encountered with VDSL transmission systems, is that upstream FEXT produced by system users having short wires can be very strong. Users having shorter wires get high bit rates whereas users having longer wires get low bit rates. In extreme cases it may happen that users with wire lengths greater than 1000 meter cannot transmit data upstream. The present invention provides a VDST transmission system with a plurality of modems. The modems are located at varying distances from a central station. There is a target bit rate for each modem. That modems on shorter wires have control means for reducing their transmit power. This reduces the FEXT produced by these modems enabling modems on longer wires to transmit at higher bit rates.