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:
Apr. 24, 2012
Filed:
Dec. 06, 2007
Satomi Shioiri, Minato-ku, JP;
Kiyoshi Fukuchi, Minato-ku, JP;
Toshiharu Ito, Minato-ku, JP;
Hitoshi Takeshita, Minato-ku, JP;
Satomi Shioiri, Minato-ku, JP;
Kiyoshi Fukuchi, Minato-ku, JP;
Toshiharu Ito, Minato-ku, JP;
Hitoshi Takeshita, Minato-ku, JP;
NEC Corporation, Tokyo, JP;
Abstract
The present invention provides a light receiving apparatus using the DQPSK demodulation method. The light receiving apparatus comprises: one Mach-Zehnder interferometer for branching a received light signal into light signals at two arms to allow the branched two light signals to interfere with each other; one balanced photoelectric converter for converting the two interfered light signals, by using the Mach-Zehnder interferometer, into an electric signal corresponding to a difference between light intensities of the two light signals; and a phase adjuster for dynamically shifting the phase of a light signal passed through one of the two arms at the Mach-Zehnder interferometer.