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:
Oct. 17, 2006
Filed:
May. 06, 2002
Yeun Chol Jung, Daejon, KR;
Cheon Joo Yoon, Daejon, KR;
Seung Gyun Shin, Seoul, KR;
Keun Joo Park, Jeollanam-Do, KR;
Yeun Chol Jung, Daejon, KR;
Cheon Joo Yoon, Daejon, KR;
Seung Gyun Shin, Seoul, KR;
Keun Joo Park, Jeollanam-Do, KR;
Korea Advanced Institute of Science and Technology, Daejon, KR;
Abstract
The present invention relates to a wavelength division multiplexed (WDM) apparatus for monitoring optical frequencies, allowing optical channel frequency monitoring using the crossover property of an arrayed-waveguide grating and pilot tones that are in wide use in optical communication networks and enhancing efficiency of operation, maintenance, and management of WDM optical communication networks. The present invention provides a WDM apparatus for monitoring optical frequencies comprising optical demultiplexing means for optically demultiplexing optical signals including externally added pilot tone signals, photo-detecting means for photo-electrically converting the output of said optical demultiplexing means, and frequency estimating means for estimating the frequency of the optical signals by measuring the amplitudes of the pilot tones from the output of said photo-detecting means.