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:
Jul. 27, 1976
Filed:
Feb. 07, 1975
Francis P Carrubba, North Haven, CT (US);
Peter A Franaszek, Ossining, NY (US);
David D Grossman, Yorktown Heights, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
In a delta modulator a sequence of code symbols are generated which are indicative of increments of signal level, with each code symbol being determined in accordance with the difference in signal level between an input signal and a prediction signal which is a representation of the input signal. A sequence of the generated code symbols are stored, including the most recent code symbol and a preceding number of code symbols, with the pattern of code symbols at any instant defining a state of signal activity. There is a table of delta increments, a table of threshold values, and a digital gain logic network, all of which provide signal outputs which are controlled by the state of signal activity represented by the stored code signal pattern. The signal output from the delta table and the threshold table are modified an amount determined by the value of the signal output from the digital gain logic network. An accumulation of modified delta increments are summed with modified threshold values for providing the prediction signal. The prediction signal and the input signal are compared for generating a new code symbol.