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:
Jun. 15, 1999
Filed:
Apr. 18, 1997
Stephen R Wynn, Lynchburg, VA (US);
Ericsson, Inc., Research Triangle Park, NC (US);
Abstract
A method for improving linear modulation compensation at the antenna terminals of an RF device in order to react to high voltage standing wave ratio variations is disclosed. In the present RF transmitters, such as portable radios, when transmission voltage standing wave ratio varies such that the linearization of its modulation technique is adversely affected, the dynamic accommodation of the variations in voltage standing wave ratio can be imposed on the output of the RF power amplifier to ensure that linearization is not lost. Specifically, the reverse power signal from the power amplifier can be detected and used to calculate a standing wave control signal. The standing wave control signal is provided to a step attenuator which attenuates the output of the power amplifier in an amount commensurate with the amount of reverse power signal at the output of the power amplifier. By adding attenuation in response to increases in reverse power signal, the linearity of the modulation being used can be controlled.