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:
Aug. 03, 2004
Filed:
Aug. 14, 2000
Masakazu Shigehara, Yokohama, JP;
Hiroo Kanamori, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
The present invention relates to a branch line monitoring system and branch line monitoring method comprising a configuration which improves the S/N ratio of measurement information and can be realized inexpensively. This system is provided with optical filters which correspond to optical fiber lines to be monitored as branch lines. These optical filters each have such a cutoff characteristic as to cut of f respective one channel of monitor light but transmit therethrough the remaining monitor light and signal light. When the optical filters having such a cutoff characteristic are provided, each of the optical fiber lines is monitored by use of a plurality of channels of monitor light other than the one cut off by the optical filter provided so as to correspond thereto. Consequently, as compared with the case where one optical fiber line is monitored by its corresponding one channel of monitor light, the S/N ratio of measurement information is improved, whereby highly accurate monitoring is possible.