Patent · US Expired

Integrated noise cancellation and residual echo suppression

US7027591B2 · kind B2 · utility

12Cited by
8References
61Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 16, 2002
Grant dateApr 11, 2006
Priority date
Expiry dateMar 8, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M9/082
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A combined processor, such as might be used in a mobile handset or hands-free communication device, provides residual echo suppression and noise reduction while eliminating the need for explicit comfort noise generation. Operating within a near-end communication device, the processor receives an echo-canceled signal that is derived from a near-end input signal, and generates an output signal for subsequent transmission to a far-end communication device by applying a noise attenuation factor to the echo-canceled signal or to an average of that signal. The processor maintains the average signal across periods of speech and non-speech. During far-end-modes of operation, where only incoming audio from the far-end is active, the processor substitutes the average signal for the echo-canceled signal, such that a far-end listener receives the natural sounding average signal without receiving the objectionable, residual echo that may be in the echo-canceled signal.

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