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:
Sep. 06, 2022
Filed:
Dec. 03, 2019
Applicant:
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Inventors:
Hirotaka Ono, Musashino, JP;
Koki Shibahara, Musashino, JP;
Takayuki Mizuno, Musashino, JP;
Yutaka Miyamoto, Musashino, JP;
Assignee:
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B 10/291 (2013.01); H04B 10/2581 (2013.01); H04J 14/04 (2006.01);
U.S. Cl.
CPC ...
H04B 10/291 (2013.01); H04B 10/2581 (2013.01); H04J 14/04 (2013.01);
Abstract
An optical repeater in a mode-division-multiplexing (MDM) optical transmission system prevents a signal-to-noise ratio (SNR) from deteriorating due to a loss of a mode demultiplexer. The optical repeater in the MDM optical transmission system is configured to include at least one multimode optical amplifier, a mode demultiplexer, a mode multiplexer, and variable optical attenuators. One of the multimode optical amplifiers is disposed on the input side of the mode demultiplexer.