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:
Aug. 11, 2009
Filed:
May. 31, 2002
Xiaoli Fu, Nepean, CA;
Genzao Zhang, Ottawa, CA;
Feng Shi, Kanata, CA;
Tongqing Wang, Los Altos, CA (US);
Jinghui LI, San Jose, CA (US);
Xiaoli Fu, Nepean, CA;
Genzao Zhang, Ottawa, CA;
Feng Shi, Kanata, CA;
Tongqing Wang, Los Altos, CA (US);
Jinghui Li, San Jose, CA (US);
Oplink Communications, Inc., Fremont, CA (US);
Abstract
A method and an apparatus for implementing carrier suppressed data format on conventional OTDM modules is provided. Adaptive phase shifting of optical signals traversing one of the tributaries of an OTDM module is performed with feedback loop control. A tapped portion of the input carrier signal is phase modulated at a frequency f, and is combined with a tapped portion of the output from the OTDM. A phase shifter controller fed with this combined signal photodetects and band-pass filters the signal around fto extract the amplitude of the AC component of the envelope of the combined signal, which depends upon the phase difference between successive pulses of the OTDM output. This signal is used to control a phase shifter coupled along one of the tributaries of the OTDM to adjust the phase difference of the signals of the two tributaries so that carrier suppression results.