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:
Dec. 19, 2017
Filed:
Dec. 14, 2016
Alcatel-lucent Usa Inc., Murray Hill, NJ (US);
Noriaki Kaneda, Westfield, NJ (US);
Alcatel-Lucent USA Inc., Murray Hill, NJ (US);
Abstract
A coherent optical receiver that is capable of obtaining separate estimates of the I/Q phase imbalances caused by the front-end circuits of the receiver and transmitter. In an example embodiment, the receiver's I/Q imbalance is estimated using equalization coefficients of a first digital equalizer located upstream from the carrier-recovery module in the train of digital-signal processing implemented at the receiver, whereas the transmitter's I/Q imbalance is estimated using equalization coefficients of a second digital equalizer located downstream from the carrier-recovery module. The receiver DSP can then use the first estimate to carry out signal processing that reduces adverse effects of the receiver's I/Q imbalance on data recovery at the receiver. The receiver can also provide the estimate of the transmitter's I/Q phase imbalance to the transmitter, which can then perform digital signal pre-distortion directed at compensating that I/Q imbalance at the transmitter.