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:
Jul. 03, 2007
Filed:
Sep. 12, 2002
Kazushige Sawada, Tokyo, JP;
Kazuo Kubo, Tokyo, JP;
Takashi Mizuochi, Tokyo, JP;
Hideo Yoshida, Tokyo, JP;
Hachiro Fujita, Tokyo, JP;
Katsuhiro Shimizu, Tokyo, JP;
Junichi Abe, Tokyo, JP;
Kazushige Sawada, Tokyo, JP;
Kazuo Kubo, Tokyo, JP;
Takashi Mizuochi, Tokyo, JP;
Hideo Yoshida, Tokyo, JP;
Hachiro Fujita, Tokyo, JP;
Katsuhiro Shimizu, Tokyo, JP;
Junichi Abe, Tokyo, JP;
Mitsubishi Denki Kabashiki Kaisha, Tokyo, JP;
Abstract
An optical receiver includes a soft-decision deciding unit () for deciding an electric received signal according to a plurality of decision levels to output a multivalued decision signal, a demultiplexing unit () for serial-to-parallel converting the multivalued decision signal to output a multivalued parallel signal, a soft-decision error correction decoding unit () for correcting the multivalued parallel signal based on reliability information to output an error-corrected parallel received signal and decision results indicating the decision of the electric received signal according to the plurality of decision levels, a probability density distribution estimation unit () for estimating probability density distributions based on distributions of the decision results, and a decision level control unit () for controlling the plurality of decision levels based on the probability density distributions, thereby improving the transmission quality.