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:
Apr. 17, 2001
Filed:
Apr. 27, 2000
Chris Wilhelm Barnard, Orleans, CA;
Chung Yu Wu, Kanata, CA;
Nortel Networks Limited, Montreal, CA;
Abstract
A method of equalizing the channels of a WDM link comprises identifying an error threshold level BER,for the BER defined for each signal S(j) in accordance with the channel rate, and determining the attenuation A(j) of, for example, the power P(j) of each signal S(j) transmitted over the WDM link. The transmitter powers are adjusted taking into account the attenuations determined for all channels. The attenuation A(j) for channel (j) is determined by first setting the power P(j) of all signals S(j) to a maximum P,, attenuating the power P(j) of channel (j) until the BER reaches the threshold value BER,, measuring the power corresponding to the BER,for that channel, and calculating the difference between the P,and P(j),. The transmitter powers are then set according to the relationship P(j)=P,−&eegr;(A(j)−A,), where &eegr; is 0.8 for a system with 3-4 channels. The method may be used for multi-channel systems with intermediate nodes where channels are added and dropped.