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:
Apr. 11, 1995
Filed:
Aug. 05, 1991
Kazuhiro Kondo, Fuchu, JP;
Masashi Ohno, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a speech packet transmission system, a transmitter (speech terminal) first linearly predicts a speech signal input at a predetermined sample period from the input signal in the past and outputs the difference between the input speech signal and the prediction signal. A prediction coefficient used for linear prediction at this time is adapted with an output differential coded value at each predetermined sample period such that the prediction value is as close as possible to the value of the input waveform. The difference between the input speech signal and the prediction signal is converted to a differential code. A packet is prepared from a plurality of differential codes obtained during a frame period concerned and transmitted to a transmission line. A bit accuracy indicative of the differential code and a bit accuracy indicative of the differential coded value used for adaptation of the prediction coefficient are changed depending on the nature or property of the input speech signal.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile