MULTI-BAND POWER AMPLIFIER AND POWER AMPLIFICATION METHOD

摘要

A multi-band power amplifier and a method thereof are provided to support two frequency bands through one power amplifier by selecting the reference value of a control voltage used in bias adjustment according to the kinds of input signals. A multi-band power amplifier includes an input signal detection unit(100), a band selection unit(110), a variable bias control unit(120), and a power amplifying unit(130). The input signal detection unit detects and outputs the amplitude of an input signal. The band selection unit outputs a control voltage which adjusts a reference voltage based on the amplitude of the input signal. The reference voltage is selected according to the kind of the input signal. The variable bias control unit adjusts and outputs a bias in response to the control voltage. The power amplifying unit amplifies the input signal based on an amplification gain adjusted according to the bias.