Patent · US Expired

Speech recognition microcomputer

US4388495A · kind A · utility

21Cited by
29References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 1, 1981
Grant dateJun 14, 1983
Priority date
Expiry dateMay 1, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10L15/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A simplified, speaker independent, selected vocabulary, word recognizing microcomputer functions without the use of a typical front end filtering network. The microcomputer identifies vowel-like fricative-like, and silence signal states within a word or phrase by counting speech pattern zero crossings during sequential time periods. Variable zero crossing count thresholds are used to identity states based upon previously identified states, and histeresis is provided, through the use of state time measurement, to prevent state oscillations which would result in erroneous state sequences. The microcomputer, by monitoring zero crossings, defines words as a sequence of vowel-like, fricative-like, and silence states. By limiting the recognizable vocabulary to words which have dissimilar sequences, the incoming speech pattern may be recognized by comparison with state templates defining the limited vocabulary stored in the microcomputer's memory.

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