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. 16, 1985
Filed:
Nov. 29, 1982
Stuart J Lipoff, Newton, MA (US);
Arthur D. Little, Inc., Cambridge, MA (US);
Abstract
FSK demodulator apparatus in accordance with the teachings of the present invention is provided wherein the input signal to be demodulated is phase compared with a plurality of reference phases of the mark and space frequencies to be detected to bracket the input signal within a particular quadrant for the frequency involved. The results of each phase comparison are then integrated with respect to time and threshold compared in such a manner that one or more phase comparison outputs, each having a duty cycle not equal to 50%, will be produced for the frequency involved, resulting in an output from the threshold comparison. This output may then be employed to establish a logic condition indicative of the frequency then being received.