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. 20, 2004
Filed:
Oct. 21, 2002
Brian Lee Heffner, Los Altos, CA (US);
Robert R. McLeod, Morgan Hill, CA (US);
JDS Uniphase Corporation, San Jose, CA (US);
Abstract
The invention relates to a simple and relatively inexpensive way of determining the optical bit rate of an optical signal, which is based on the fact that different percentages of the signal will be transmitted through a narrow-band optical filter depending on the bit rate. Increasing the bit rate of an optical signal results in a broadening of the channel spectrum, therefore, if the optical filter is designed with a passband thinner than all (or all but one) of the channel widths, then signals with different bit rates will have distinctive amounts of transmitted light relative to the amount of input light. In the preferred embodiment the optical signal is divided into two sub-beams by a beam splitter, and one of the sub-beams is passed through the optical filter. The power of filtered sub-beam is compared to the power of the unfiltered sub-beam to provide a ratio, which is compared to one or more predetermined values indicative of the bit rate. The optical filter is preferably a Fabry-Perot etalon with a periodic response tuned to the ITU grid.