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:
Mar. 21, 2000
Filed:
Dec. 19, 1997
Nortel Networks Corporation, Montreal, CA;
Abstract
A method and apparatus for channel performance equalization in wavelength division multiplexed (WDM) systems is disclosed. Performance of the channels is estimated from optical power measurements of each signal transmitted by the channels. The measurements are taken at the inputs of optical amplifiers in the transmission path of the system. The channels are equalized by adjusting the optical power of the channel transmitters. The method is applicable to point-to-point networks as well as more complex network configurations such as those having an add-drop multiplexer (ADM) for inserting and extracting channels from the transmission path. The method can compensate for signals having different bit rates by applying an offset to the amount of optical power adjustment of the channel transmitters. Furthermore, if different types of optical amplifiers are used in the transmission path, the method can accommodate different noise characteristics of the amplifiers by using their noise figures in determining the amount of optical power adjustment of the transmitters that is required to equalize channel performance.