| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-frequency amplifier capable of attaining high efficiency and small circuit size while accommodating burst operation and continuous operation even at low output power. SOLUTION: The high-frequency amplifier includes: a switching device 5 for switching between an envelopment signal and a burst signal of an RF signal input into this device; a pulse duration modulator 1 for generating a pulse duration modulation wave based on either one of the envelopment signal and the burst signal from the switching device 5; a switching amplifier 2 for amplifying a pulse duration modulation wave; a low-pass filter 3 that passes a low-frequency output signal of the switching amplifier 2; and an RF amplifier 4 that has an input terminal 4a, an output terminal 4b and a power terminal, inputs an output from the low-pass filter 3 from the power terminal as a power supply bias, amplifies an RF signal input into the input terminal 4a and outputs the amplified signal from the output terminal 4b. COPYRIGHT: (C)2012,JPO&INPIT |
