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:
Dec. 24, 1985
Filed:
Sep. 20, 1982
Applicant:
Inventor:
Dimitrios P Prezas, Chicago, IL (US);
Assignee:
AT&T Bell Laboratories, Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G10L / ;
U.S. Cl.
CPC ...
381 49 ;
Abstract
Speech signal pitch detection uses the residual signal output of an LPC (linear prediction coder) filter. The residual signal (or its Hilbert transform) is divided into frames of 20 milliseconds, and each frame searched for signal peak periodicity by first detecting the highest peak, then detecting a set of equally-spaced selected samples from which the pitch period is determined. If no periodicity is found over three frames, an unvoiced decision is made.