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:
Mar. 15, 2022
Filed:
Aug. 31, 2020
Wing Chau NG, Stittsville, CA;
Xuefeng Tang, Kanata, CA;
Zhuhong Zhang, Ottawa, CA;
HUAWEI TECHNOLOGIES CO., LTD., Shenzhen, CN;
Abstract
Methods and apparatuses for IQ time skew calibration in a coherent transceiver are described. A four-channel signal is received. A set of inputs is constructed for a 4×8 MIMO equalizer by converting the four-channel signal into four complex inputs that each have a phase shift corresponding to an estimated carrier frequency offset. The set of inputs further includes conjugate replicas of the four complex inputs. Using output from the 4×8 MIMO equalizer, equalizer coefficients are calculated by minimizing error between the MIMO output and a reference signal. Receiver and transmitter IQ skew are estimated using the equalizer coefficients, by converting the equalizer coefficients form the time domain to the frequency domain to determine receiver and transmitter IQ differential phase responses, which are indicative of respective receiver and transmitter IQ skew in the time domain. Skew compensation is then performed.