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:
May. 22, 2012
Filed:
Dec. 14, 2009
Koji Terada, Kawasaki, JP;
Koji Terada, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical receiving circuit receives and demodulates an optical signal subjected to phase modulation and wavelength division multiplexing. The optical receiving circuit includes an interfering unit that causes a reference signal to interfere with the optical signal to output resulting signals as positive-phase signals and negative-phase signals; and a wavelength separator having input ports receiving the positive-phase signals and the negative-phase signals, the positive-phase and negative-phase signals being adjacent to each other. The wavelength separator separates according to wavelength, the positive-phase signals and the negative-phase signals, and from output ports, outputs for each wavelength, a separated positive-phase signal and negative-phase signal in a state of being adjacent to each other. The optical receiving circuit further includes balanced receivers respectively provided for each wavelength, where a given balanced receiver for a given wavelength performs balanced reception and demodulation of the separated positive-phase signal and negative phase signal of the given wavelength.