The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 1986
Filed:
Aug. 21, 1985
Kazunori Noso, Yokosuka, JP;
Norimasa Kishi, Yokohama, JP;
Abstract
A speech recognition system for an automotive vehicle derive a spoken instruction start signal and a spoken instruction end signal when a smoothed spoken instruction signal exceeds or drops below a predetermined threshold level representing the intensity of the background noise for more than first and second predetermined time periods, respectively. Noise is determined by converting the output of a microphone transducing the spoken instruction into a single polarity signal that is smoothed with a long time constant. The single polarity variation is also smoothed with a shorter time constant. The signals with the long and short constants are applied to a comparator that derives a bi-level output signal. In response to transitions in first and second directions of the bi-level signal lasting for first and second durations, the start and end signals are respectively derived.