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:
Apr. 24, 2007
Filed:
Jul. 29, 2003
Toshimitsu Matsuyoshi, Osaka, JP;
Toshimitsu Matsuyoshi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A power amplifier comprises an amplifier amplifying a high-frequency signal modulated by an input signal. An inverted envelope generates circuit generating an inverted envelope signal by using the input signal or the high-frequency signal The inverted envelope signal having an inverted envelope. A variable gain amplifier adjusts the amplitude of the inverted envelope signal, and a variable delay circuit adjusts a phase of the inverted envelope signal. A control circuit outputs a control signal to the variable gain amplifier and the variable delay circuit based on information about distortion or a signal level of the amplified high-frequency signal. The inverted envelope signal having been adjusted in amplitude or phase is injected to the high-frequency signal or the amplified high-frequency signal. The control circuit controls the variable gain amplifier or the variable delay circuit so that distortion or a signal level of the amplified high-frequency signal is minimum.