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:
Sep. 20, 2022
Filed:
Nov. 11, 2021
Tung Trong Nguyen, Kanata, CA;
Timothy James Creasy, Manotick, CA;
Shahab Oveis Gharan, Ottawa, CA;
CIENA CORPORATION, Hanover, MD (US);
Abstract
Upon receiving a communications signal conveying symbols at a symbol period T, a receiver applies filter coefficients to a digital representation of the communications signal, thereby generating filtered signals having a shape in the frequency domain characterized by a bandwidth expansion factor α, where components of the filtered signals correspond to angular frequencies The receiver calculates first-order components from a first phase derivative of the components at a first differential distance, second-order components from a second phase derivative of the first-order components at a second differential distance, and composite second-order components from an average of the second-order components over multiple time intervals. Using the composite second-order components, the receiver calculates at least one of (i) an estimate of residual chromatic dispersion (CD) associated with the filtered signals, and (ii) an estimate of carrier frequency offset (CFO) associated with the filtered signals.