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:
May. 29, 2001
Filed:
Dec. 05, 1997
James Harley, Ottawa, CA;
Richard A. Habel, Ottawa, CA;
Nortel Networks Limited, Montreal, CA;
Abstract
The power of an optical signal (s,) travelling on a channel (&lgr;,) of a WDM transmission system, is measured using a signature bit pattern (s,) which is inserted in the frame of the optical signal (s,). The power level of s,is adjusted at the launching point to a predetermined ratio (m) with the power of the optical signal. At a point of interest, the fiber is tapped and a fraction of the tapped signal, that includes a corresponding fraction of s,, is converted to an electrical signal. The fraction of s,is extracted from a the electrical signal and power of s,is measured. This gives the optical power of s,as (m) is known and also the calibration constant for the respective channel (&lgr;,) is known. The method can be applied for any and all channels of the WDM transmission system.