Patent · US Expired

Digital speech detector

US4028496A · kind A · utility

65Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 17, 1976
Grant dateJun 7, 1977
Priority date
Expiry dateAug 17, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04J3/175
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The detection sensitivity and noise rejection of an arrangement for detecting speech in the presence of noise is improved by accumulating the weighted differences between input signal samples and their short-term running average. The detector thus tracks ambient noise, providing an adaptive detection threshold such that detection sensitivity is increased in low noise environments without excessive false operation on high level noise. The peak average attained during an interval of speech is used to provide variable hangover upon cessation of speech, yielding greater hangover for weak talkers than for loud talkers. In an illustrative embodiment of the speech detector used in a speech interpolation system, protection is afforded also against false transmission path operation due to detection of speech echo.

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