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. 01, 1980
Filed:
Jul. 18, 1978
Harold G Nash, Tempe, AZ (US);
John R Linford, Broomfield, CO (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A method and an apparatus are disclosed which employ digital techniques to approximate a multiplication of an analog signal by a sine wave of an appropriate frequency for detecting the analog signal. The analog signal is converted to a digital representation which includes a binary sign bit and a plurality of binary magnitude bits. The sign bit of the digital representation is selectively complemented by an inverting logic gate which operates under the control of a square wave having the appropriate frequency of the sine wave which is being approximated. The selective complementation of the sign bit of the digital representation functions to multiply the digital representation by +1 or -1 as determined by the status of the square wave signal. The resulting digital representation is latched at periodic intervals for further processing of the detected signal which results from the quasi digital multiplication.