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. 28, 2018
Filed:
Nov. 30, 2016
Applicant:
Fujitsu Limited, Kawasaki-shi, Kanagawa, JP;
Inventors:
Yuichi Akiyama, Kawasaki, JP;
Hisao Nakashima, Kawasaki, JP;
Assignee:
FUJITSU LIMITED, Kawasaki, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B 10/079 (2013.01); H04B 10/548 (2013.01); H04B 10/564 (2013.01);
U.S. Cl.
CPC ...
H04B 10/548 (2013.01); H04B 10/0795 (2013.01); H04B 10/564 (2013.01);
Abstract
A signal shifted from a carrier frequency in a frequency domain by using digital signal processing is generated, and the optical modulator is driven with a drive signal based on the signal. A monitor monitors whether or not a component of a modulated signal light output from the optical modulator appears in a specific frequency depending on a frequency shift performed by the digital signal processing, and the controller controls a relation between a sign of the drive signal and an operating point of the optical modulator according to a monitored result.