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. 26, 2022
Filed:
May. 15, 2019
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Hiroto Kawakami, Tokyo, JP;
Shoichiro Kuwahara, Tokyo, JP;
Yoshiaki Kisaka, Tokyo, JP;
Masanori Nakamura, Tokyo, JP;
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo, JP;
Abstract
A control processor performs, in a startup sequence of an IQ optical modulator using a nested MZI, a first-stage process of controlling, so that a signal quality of an optical QAM signal output from a monitor port of the IQ optical modulator approaches a target quality, a voltage applied by a Bias_I voltage generator to I-component MZ optical modulator, a voltage applied by a Bias_Q voltage generator to a Q-component MZ optical modulator, and a voltage applied by a Bias_Ph voltage generator to a Bias_Ph phase adjusting means for controlling an optical path length of a parent MZI. After a completion of the first-stage process, the control processor changes a voltage output from the Bias_Ph voltage generator by a predetermined amount.