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. 30, 2012
Filed:
Dec. 19, 2008
Ilija Hadzic, Millington, NJ (US);
Dennis Raymond Morgan, Morristown, NJ (US);
Alf Neustadt, Stuttgart, DE;
Zulfiquar Sayeed, Hightstown, NJ (US);
Ilija Hadzic, Millington, NJ (US);
Dennis Raymond Morgan, Morristown, NJ (US);
Alf Neustadt, Stuttgart, DE;
Zulfiquar Sayeed, Hightstown, NJ (US);
Alcatel Lucent, Paris, FR;
Abstract
An endpoint or other communication device of a communication system includes a clock recovery module. The communication device is operative as a slave device relative to another communication device that is operative as a master device. The clock recovery module comprises a clock recovery loop configured to control a slave clock frequency of the slave device so as to synchronize the slave clock frequency with a master clock frequency of the master device. The clock recovery loop utilizes a frequency error estimator implemented as a maximum-likelihood estimator with slope fitting based on a sequence of arrival timestamps, and a loop filter implemented as a series combination of an adaptive-bandwidth filter and a proportional-integral controller. The clock recovery module may further comprise a discontinuity detector configured to detect a discontinuity in delays of respective timing messages, and a loop controller operative to place the clock recovery loop in a particular state responsive to detection of the discontinuity.