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:
Nov. 25, 2008
Filed:
Nov. 16, 2004
John Feng, Union City, CA (US);
Xuehua Wu, Union City, CA (US);
Sanjai Parthasarathi, Los Altos, CA (US);
Giovanni Bararossa, Saratoga, CA (US);
John Feng, Union City, CA (US);
Xuehua Wu, Union City, CA (US);
Sanjai Parthasarathi, Los Altos, CA (US);
Giovanni Bararossa, Saratoga, CA (US);
Avanex Corporation, Fremont, CA (US);
Abstract
A group delay compensation equalizer is disclosed that employs a single channel four-port WDM device for compensating the group delay experienced by a plurality of wavelengths transmitted over different paths. The transmission differential between two wavelengths is compensated by transmitting the two wavelengths through two different paths where the fiber length in reflecting the second wavelength is equal to the transmission time difference between the two wavelengths. The single channel four-port group delay equalizer effectively provides a unidirectional signal flow, as compared to the conventional equalizer that transmits optical signals bi-directionally. The present invention reduces the cost of a group delay equalizer by simplifying the use of multiple three-port WDM devices into a single channel four-port WDM device. The present invention further reduces the number of alignments required to just one on the transmission side since the group delay equalizer now has one transmission output, rather than two transmission outputs in a prior solution.