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:
Nov. 22, 1977
Filed:
Jun. 30, 1976
Gardner Dulany Jones, Jr, Raleigh, NC (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A companded digital delta modulator which can encode both voice and voice band modem signals over a wide range of input levels is shown. The companding method or algorithm is based on measuring bit stream correlation and can be scaled to give substantially maximum performance over a wide range of signal types. The algorithm has a low sensitivity to digital channel errors, thus making it suitable for signal coding for satellite channels and the like. In addition, the digital design permits common hardware to simultaneously serve a large number of lines, thus permitting the substantial savings in the hardware cost per line. A further aspect of the invention concerns the ability to handle multiple bit delta modulation as well as single bit delta bit modulation in the above environment.