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:
Oct. 14, 2008
Filed:
Mar. 05, 2004
Hiroyuki Deguchi, Kawasaki, JP;
Shinichirou Harasawa, Kawasaki, JP;
Hideki Maeda, Yokohama, JP;
Akira Naka, Yokosuka, JP;
Gentaro Funatsu, Yokohama, JP;
Hiroyuki Deguchi, Kawasaki, JP;
Shinichirou Harasawa, Kawasaki, JP;
Hideki Maeda, Yokohama, JP;
Akira Naka, Yokosuka, JP;
Gentaro Funatsu, Yokohama, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The present invention provides an automatic power restoring method capable of reliably detecting continuity by the dissolution of a line fault, to restore the optical power, even in a structure including an optical amplification medium on an optical transmission path and an optical communication system using the method. To this end, in an optical communication system to which the automatic power restoring method of the invention is applied, a pilot signal having a low transmission rate, a wavelength of which is set based on loss wavelength characteristics obtained by combining loss wavelength characteristics of an optical fiber used for the optical transmission path and loss wavelength characteristics of the optical amplification medium on the optical transmission path, is transmitted and received between an optical transmitting station and an optical receiving station when a line fault occurs, and a detection of continuity is thus performed. According to the result of the continuity detection, the power state at the occurrence of line fault is automatically restored to the power state at a time of normal operation.