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:
Jun. 28, 2005
Filed:
Mar. 07, 2003
Alexander Beger, Bridgewater, NJ (US);
Ranjan Dutta, Lawrenceville, NJ (US);
Mitchell E. Haller, Marlboro, NJ (US);
Shuai Shen, East Brunswick, NJ (US);
Alexander Beger, Bridgewater, NJ (US);
Ranjan Dutta, Lawrenceville, NJ (US);
Mitchell E. Haller, Marlboro, NJ (US);
Shuai Shen, East Brunswick, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
A channel detection system includes an interferometer coupled to a spectrum analyzer to differentiate additive spontaneous emission (ASE) noise from optical channels in a dense wave-division multiplex (DWDM) signal. It is assumed that channels, if present, are centered at frequencies corresponding to a standardized channel grid. The relative delay of the interferometer is chosen to be greater than the coherence time of the ASE noise but less than the coherence time of the channels with the interferometer's free spectral range set to an integer divisor of the channel-to-channel frequency spacing of the grid such that active channels experience a high degree of interference. The phase delay of the interferometer is then adjusted to maximize the interference at each grid-aligned frequency. The spectrum-analyzed outputs are compared (e.g., subtracted from one another and then thresholded) to determine the channels present in the DWDM signal.