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. 19, 2024
Filed:
Feb. 05, 2021
Nec Corporation, Tokyo, JP;
Akira Masuda, Tokyo, JP;
NEC CORPORATION, Tokyo, JP;
Abstract
A fault detection apparatus includes: a transmitter that transmits a first optical signal through an optical transmission line; a receiver that receives, in response to the transmission of the first optical signal, a second optical signal from the line, and measures the reception level of the second optical signal; and a control unit that specifies a section where the second optical signal corresponding to the first optical signal was generated, calculates an optical level corresponding to a loss in said section on the basis of the reception level, determines that a first fault has occurred in the section when the optical level in the section has changed from a first reference level by a first threshold or more, sets a second reference level and a second threshold after occurrence of the first fault, and determines occurrence of a second fault.