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. 29, 1991
Filed:
Feb. 28, 1989
Michael J Serrone, Sunnyvale, CA (US);
First Pacific Networks, Sunnyvale, CA (US);
Abstract
A method and an apparatus for demodulating M-ary PSK signals of the type wherein the modulation is limited to phase transitions between adjacent phase states. The method is operative in a demodulator which comprises a phase splitter dividing a source signal into two paths with a preselected phase relationship among phases, one of the phases being delayed by nominally one bit period, a mixer or multiplier receiving as one input a representation of the delayed-phase component and as a second input a representation of the other phase component. A signal is filtered by a lowpass filter and provided to at least one corresponding two-level comparator, each of which produces a digital output. Digital logic circuitry responds to the digital outputs of each of the comparators to map the digital outputs into a single digital bit stream of ones and zeros.