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. 06, 2003
Filed:
Jan. 14, 1999
Kevin Stuart Farley, Bishop's Stortford, GB;
Richard Edward Epworth, Sawbridgeworth, GB;
Daniel Watley, Cambs, GB;
Nortel Networks Limited, St. Laurent, CA;
Abstract
A method of compensating the polarisation mode dispersion (PMD) of an optical transmission path carrying clocked digital data traffic involves modulating the state of polarisation (SOP) of the light launched into the transmission path, and employing consequential frequency components in an electrical signal detected at the far end of the transmission path to regulate the birefringence of a polarisation state controller portion of a birefringent element inserted between the transmission path and the receiver's photodetector. The SOP modulation, when represented on a Poincaré sphere, has an oscillatory rotational component at a frequency f about a first axis of the sphere and an oscillatory rotational component at a frequency f about a second axis of the sphere that is orthogonal to said first axis, and where f ≠f , f ≠2f , and f ≠2f .