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:
May. 29, 1990
Filed:
Dec. 19, 1988
Kenzo Kobayashi, Kawasaki, JP;
Yutaka Iwagaki, Yokosuka, JP;
Mitsuyo Hasegawa, Tokyo, JP;
Kazushi Suganuma, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
Disclosed is a duplex system of transmission lines in a loop network applied, for example, to a local area network. To realize an autonomous recognition of transmission line faults by each communication node and to enable a rapid and automatic reconstruction of a network, each communication node comprises a loop back circuit for effecting a loop back operation in response to a predetermined state of signals received from two directions of the duplex loop lines, and a return indication circuit for adding, to a transmitted signal a return indication that a received signal was returned when the received signal could not be passed through the node.