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:
Nov. 15, 2016
Filed:
Sep. 24, 2014
Fujitsu Limited, Kawasaki-shi, JP;
Kazuhiko Hatae, Kawasaki, JP;
Nobukazu Koizumi, Kawasaki, JP;
Koji Nakamuta, Yokohama, JP;
Manabu Yamazaki, Fuchu, JP;
Tomoki Katou, Kawasaki, JP;
Masashi Sato, Kawasaki, JP;
Hisao Nakashima, Kawasaki, JP;
FUJITSU LIMITED, Kawasaki, JP;
Abstract
A receiving device that converts, to a digital signal, a signal in which signal light from an optical transmission path and local oscillation light are mixed, so as to perform digital signal processing, the optical communication receiving device comprising: a frequency offset compensation unit configured to calculate a frequency offset of the digital signal and to, based on the frequency offset, compensate for a phase of the digital signal; a carrier phase recovery unit configured to calculate a carrier phase of the digital signal whose phase is compensated for in the frequency offset compensation unit; and a residual frequency offset detection unit configured to calculate an average of differences in the carrier phase, and to output the average as a residual frequency offset, wherein the frequency offset compensation unit is configured to correct the frequency offset using the residual frequency offset output by the residual frequency offset detection unit.