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. 10, 2002
Filed:
Dec. 20, 1999
Paul H. Gailus, Prospect Heights, IL (US);
William J. Turney, Schaumburg, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A method and apparatus is provided that amplitude modulates a modulated radio frequency (RF) signal ( ) by modulating the supply voltage of a power amplifier ( ). The method and apparatus further provides an impedance modulator ( ) that reduces output signal ( ) errors in response to an error signal generated by a feedback circuit ( ) that includes a quadrature modulator ( ), a limiter ( ), a comparator ( ), and a quadrature downconverter ( ). Intermodulation distortion generated in the feedback circuit ( ) by delay mismatches between amplitude and phase feedback paths, and non-linear effects of AM/PM conversion in a limiter ( ), are suppressed by placing limiter ( ) and quadrature downconverter ( ) in a forward path of the overall amplifier loop.