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. 22, 2011
Filed:
Feb. 13, 2009
David Reed, Westminster, CO (US);
Nadim Khlat, Midi-Pyrenees, FR;
David Reed, Westminster, CO (US);
Nadim Khlat, Midi-Pyrenees, FR;
RF Micro Devices, Inc., Greensboro, NC (US);
Abstract
The present invention relates to image rejection calibration in a radio frequency (RF) receiver. In one embodiment, the receiver includes a receiver front-end and an image rejection calibration system. The image rejection calibration system provides a first test signal to an RF input of the receiver front-end, and obtains first measurements of a quadrature output signal output from the receiver front-end while the first test signal is applied to the RF input. The image rejection calibration system then applies a second test signal to the RF input of the receiver front-end that is approximately 90 degrees out-of-phase with the first test signal, and obtains second measurements of the quadrature output signal while the second test signal is applied to the RF input. Based on the first and second measurements, the image rejection calibration system determines an amplitude error and a phase error of the receiver front-end.