Patent · US Expired

Process and system for improving echo cancellation within a transmission network

US4751730A · kind A · utility

26Cited by
8References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 28, 1986
Grant dateJun 14, 1988
Priority date
Expiry dateApr 28, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B3/23
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

This process enables cancelling residual echo signals in a transmission system wherein echo signals are partially cancelled through use of a filter generating an echo replica, and substracting said replica from the signal in the echo path. The process involves measuring energies of incoming and outgoing signals, comparing the ratio of said energies to a predetermined threshold value to generate a flag information, which flag is used to control a switch on the echo path. The threshold is determined, for instance by using the information provided by the echo path impulse response not considered for the generation of the echo replica.

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