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:
Jan. 31, 1989
Filed:
Aug. 25, 1987
Applicant:
Inventor:
Charles S Weaver, Palo Alto, CA (US);
Assignee:
SRI International, Menlo Park, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G10L / ;
U.S. Cl.
CPC ...
381 35 ; 128696 ; 36441306 ; 36472419 ; 375122 ;
Abstract
Audio signals such as ECG, speech and music are digitally processed to reduce the bit-rate needed for accurate transmission, known as minimizing the entropy of the signal. The transmitter features a digital compression filter with zeros restricted to certain points on the unit circle, and Huffman encoding for transmission. The receiver features a digital decompression filter with poles at the zero locations, but shifted inside the unit circle to prevent error-ramp build-up.