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:
Jan. 04, 2011
Filed:
Nov. 10, 2005
Koji Kikushima, Chiba, JP;
Satoshi Ikeda, Chiba, JP;
Koji Kikushima, Chiba, JP;
Satoshi Ikeda, Chiba, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
In an optical transmission system by frequency-division multiplexing, the interference due to distortions of a first signal against a second signal can be reduced. In the optical transmission system where a modulated optical signal by the first signal is further modulated with the second signal for transmission, distortions of the first signal corresponding to a frequency band of the second signal is extracted. The extracted signal is phase-inverted and then adjusted in phase and amplitude with respect to the distortions of the first signal to obtain a correction signal. By intensity-modulating the first signal containing the distortions by the correction signal, the distortions of the first signal against the second signal can be cancelled out. Alternatively, by intensity-modulating the first signal containing the distortions by a combined signal of the correction signal and the second signal, the distortions of the first signal against the second signal can be cancelled out.