Patent · US Expired

Reverse channel next cancellation for MDSL modem pool

US5970088A · kind A · utility

99Cited by
15References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 31, 1996
Grant dateOct 19, 1999
Priority date
Expiry dateOct 31, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2025/03611
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A central office xDSL modem pool has N logical xDSL modems. Each modem consists of a transmitter part and a receiver part and is connected to a twisted pair subscriber loop. A central office clock synchronizes the modem transmitters. A reverse channel near-end crosstalk (NEXT) canceller bank is implemented within the modem pool. The NEXT canceller bank has N NEXT cancellers corresponding to the N MDSL modems. Each canceller has N adaptive filters of size M. Outputs of all N adaptive filters are combined to form the NEXT cancellation signal for the corresponding modem. Each adaptive filter is adapted according to the error signal between the received signal and the NEXT cancellation signal and the corresponding transmit signal as the correlation vector.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.