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. 03, 2015
Filed:
Feb. 26, 2013
Hitachi, Ltd., Tokyo, JP;
Nobuhiko Kikuchi, Tokyo, JP;
HITACHI, LTD., Tokyo, JP;
Abstract
In order to reduce the circuit size for a chromatic dispersion pre-equalization operation, an optical multilevel signal pre-equalization circuit is provided with: (1) a plurality of look-up tables in which a string of middle codes utilizing a symmetry of a signal constellation of a multilevel code or a string of middle codes represented by polar coordinates is stored in association with a waveform response component; and (2) one or more operation circuits to which the waveform response component corresponding to a multilevel signal to be transmitted is inputted from the plurality of look-up tables, and which outputs a pre-equalized output waveform corresponding to the multilevel signal by operating the waveform response components outputted from different look-up tables.