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:
Dec. 10, 2013
Filed:
Aug. 03, 2011
Kazuhiko Hatae, Kawasaki, JP;
Noriyasu Nakayama, Kawasaki, JP;
Nobukazu Koizumi, Kawasaki, JP;
Yuji Obana, Kawasaki, JP;
Kazuhiko Hatae, Kawasaki, JP;
Noriyasu Nakayama, Kawasaki, JP;
Nobukazu Koizumi, Kawasaki, JP;
Yuji Obana, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An ALC processing unit to adjust the signal level of outputs from an adaptive equalizer to a target value is provided in a stage later than the adaptive equalizer and earlier than a frequency offset estimation/compensation unit in an optical digital coherent receiver. The ALC processing unit generates a histogram that counts the number of samples for discrete monitored values corresponding to amplitude values of outputs from the adaptive equalizer, and determines a level adjustment coefficient that is to be multiplied by an output from the adaptive equalizer so as to multiply the determined coefficient by the output from the adaptive equalizer so that the monitored value of the peak value of the histogram is the target value.