Method and apparatus for monitoring channel frequency response

US7564895B2 · kind B2 · utility

Assignee

• Nortel Networks Limited · CA

Inventors

• Gin Liu · Brampton, CA
• Andrew G. Dempster · Sydney, AU
• Mike M. J. Wingrove · Gatineau, CA
• Gwendolyn Kate Harris · Ottawa, CA
• Michel M. Darveau · Aylmer, CA
• Leslie Derek Humphrey · Harlow, GB
• Mohammed Reza Pakravan · Ottawa, CA

Key dates

• Filing date: Dec 21, 2001
• Grant date: Jul 21, 2009
• Expiry date: Feb 10, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04B3/487
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

Method and apparatus for retrieving the channel frequency response H(f), the noise N(f), measured at initialization and the signal to noise ratio SNR(f) measured at show time on a per bin basis, in the upstream or downstream direction. Initialization H(f) is used for analyzing the physical copper loop condition between tip and ring. Initialization N(f) is used for analyzing the crosstalk. Showtime SNR(f) is used for analyzing time dependent changes in crosstalk levels and line attenuation. The combination of H(f), N(f) and SNR(f) allows analysis of the line conditions for reaching the maximum data rate of a given loop, scheduling maintenance and plant update.