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:
Jan. 25, 2011
Filed:
Feb. 06, 2006
Nadim Khlat, Cugnaux, FR;
Wael A. Al-qaq, Oak Ridge, NC (US);
Dennis Mahoney, High Point, NC (US);
Paul D. Brey, Chapel Hill, NC (US);
Brian Baxter, High Point, NC (US);
Nadim Khlat, Cugnaux, FR;
Wael A. Al-Qaq, Oak Ridge, NC (US);
Dennis Mahoney, High Point, NC (US);
Paul D. Brey, Chapel Hill, NC (US);
Brian Baxter, High Point, NC (US);
RF Micro Devices, Inc., Greensboro, NC (US);
Abstract
A system and method are provided for calibrating Amplitude Modulation to Phase Modulation (AM/PM) pre-distortion in a transmitter operating according to a polar modulation scheme. In general, phase modulation is disabled during transmission of an actual polar modulation signal. As a result, the transmitter provides a radio frequency (RF) output signal having an amplitude modulation component and ideally a constant phase. However, the AM/PM distortion of the transmitter creates a phase modulation component in the RF output signal. The phase component of the RF output signal, which is the AM/PM distortion of the transmitter, is measured by test equipment. The AM/PM pre-distortion applied by the transmitter is then calibrated based on the measured AM/PM distortion such that the AM/PM distortion of the transmitter is substantially reduced.