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:
Sep. 19, 1989
Filed:
Apr. 01, 1988
Taruna Tjahjadi, Norcross, GA (US);
Cynthia A Panella, Alpharetta, GA (US);
Matthew F Easley, Decatur, GA (US);
Randy D Nash, Dacula, GA (US);
Steven R Sweitzer, San Carlos, CA (US);
John N Martin, Atlanta, GA (US);
German E Correa, Marietta, GA (US);
George R Thomas, Marietta, GA (US);
Hayes Microcomputer Products, Inc., Norcross, GA (US);
Abstract
An improved V.22 bis 2400 bits per second (bps) handshake sequence detector. An incoming phase keyed (PSK) handshake sequence is autocorrelated using a frequency shift keyed (FSK) receiver (101). The autocorrelated signal is then filtered by a low pass filter (106). The autocorrelated, low pass filtered signal is then alternately fed, at a 1200 Hz rate, to two detectors (114,116). Each of the detectors (114,116) looks for one half of the handshake sequence. The output of each detector (114,116) is provided to an OR-gate (122). The 2400 bps handshake sequence is declared to be detected when either one or both of the detectors (114,116) detects its corresponding portion of the sequence.