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:
Dec. 31, 2007
Toshiki Honda, Kawasaki, JP;
Takeshi Ono, Kawasaki, JP;
Toshiki Honda, Kawasaki, JP;
Takeshi Ono, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The optical transmitter and receiver of the invention includes: a variable dispersion compensator that performs wavelength dispersion compensation on an optical signal of a differential M-phase modulation format input from a transmission path; an optical amplifier that compensates an optical loss in the variable dispersion compensator; a delay interferometer that delays and interference processes the optical signal output from the optical amplifier; and a photoelectric conversion circuit that photoelectric converts the output light from the delay interferometer to generate a demodulated electric signal. The output level of the optical amplifier is decreased at the time of start up to deteriorate the OSNR of the optical signal input to the photoelectric conversion circuit, to thereby realize a state in which an error occurs more easily, and then optimization control of the variable dispersion compensator and the delay interferometer is started. As a result optimization of the dispersion compensation amount and the phase control amount in the optical receiver corresponding to the differential M-phase modulation format can be performed in a short time.