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:
Mar. 24, 1992
Filed:
Jul. 12, 1990
Kohichi Ohno, Yokohama, JP;
Yukio Furukawa, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A polarity detector for subscriber lines in a data transmitting system which detects the polarity of 2-wire subscriber lines using 2B1Q codes. A converter converts a quaternary 2B1Q code into binary code and outputs complementary binary data. A frame synchronizing signal detector detects a binary code frame synchronizing signal in the complementary binary data and outputs a timing signal. A pattern detector detects an all '1's or '0's state of the complementary binary data and the timing signal. A selector circuit selects all complementary data having a single polarity in response to all '1's or '0's detected by the pattern detector. Therefore, correct data is received by correctly detecting the polarity of the subscriber line.