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:
Nov. 14, 2000
Filed:
Jun. 07, 1995
Fumihiro Ikawa, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical transmission system containing a protection system and a plurality of working systems. When a trouble occurs in the protection system to which one of the working system is switched, a line alarm indication signal (LINE AIS), which can be detected in a reception portion of a piece of terminal equipment, and can activate a switch control circuit, is transmitted to a piece of terminal equipment on the reception side. In response to the receipt of the line alarm indication signal (LINE AIS), the piece of terminal equipment on the reception side transmits a far end receive failure signal (FERF) through an protection system optical transmission line (PTCT2) to a piece of protection system terminal equipment on the transmission side, and transmits a path alarm indication signal (PATH AIS) which does not activate the switch control circuit, through an optical transmission line in the same terminal station to the pieces of working system terminal equipment in the same terminal station on the reception side.