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. 17, 2012
Filed:
Apr. 23, 2008
Shigehiro Takashima, Tokorozawa, JP;
Takayoshi Fukui, Yokohama, JP;
Yoshikuni Uchida, Yokohama, JP;
Kazuyoshi Yamaki, Yokohama, JP;
Youichi Honzawa, Fujisawa, JP;
Shigehiro Takashima, Tokorozawa, JP;
Takayoshi Fukui, Yokohama, JP;
Yoshikuni Uchida, Yokohama, JP;
Kazuyoshi Yamaki, Yokohama, JP;
Youichi Honzawa, Fujisawa, JP;
Opnext Japan, Inc., Kanagawa, JP;
Abstract
A technology to automatically control the biasing of an optical duobinary transmitter using a single-drive LN-MZ modulator is provided. A low-frequency signal is amplitude modulated onto a voltage signal input into a Mach-Zehnder optical modulator. The optical output from the optical modulatoris detected by an optical detection subsystem. In a bias control subsystem, the low-frequency signal component amplitude modulated onto the electrical signal is detected from the optical output, and a DC bias voltage applied to the optical modulator is controlled such that the low-frequency signal component is either minimized or maximized.