Patent ID: 8254496
Filing Date: 2012-08-28
Classification: H03F,H03G

Abstract:
1. A power amplifier for amplifying a high-frequency modulated signal, comprising: a first processing unit for amplifying an envelope signal included in the high-frequency modulated signal, said envelope signal including only an amplitude modulated component of the high-frequency modulated signal; and a second processing unit for adjusting an average power of an output signal of said power amplifier, wherein said first processing unit includes: an AD converter for converting the envelope signal to a time discrete signal; a switching amplifier for amplifying an output signal of said AD converter; a low-pass filter for removing high-frequency noise from an output signal of said switching amplifier; and a power combiner circuit, and said second processing unit includes: a plurality of high-frequency power amplifiers supplied with an output signal of said low-pass filter as a power supply for amplifying a carrier signal included in the high-frequency modulated signal, said plurality of high-frequency power amplifiers being arranged in parallel, each of said plurality of high-frequency power amplifiers being configured to amplify the carrier signal by multiplying the carrier signal by the power supply, and the power combiner circuit is configured for combining output signals of said plurality of high-frequency power amplifiers and for delivering the combined output signal to the outside; and a power controller for controlling a total gain of said plurality of high-frequency power amplifiers based on a power control signal independent of the high-frequency modulated signal to adjust an average power of an output signal of said power amplifier, said power controller being configured to conduct on/off control for said plurality of high-frequency power amplifiers to adjust an average power of the output signal of said power amplifier.