SELF MIXING ADAPTIVE BIAS CIRCUIT SYSTEM FOR A POWER AMPLIFIER, CAPABLE OF ADAPTIVELY CONTROLLING THE BIAS OF AN AMPLIFIER ACCORDING TO THE INPUT OF AN AMPLIFIER AND THE LEVEL OF AN OUTPUT POWER, AND A METHOD THEREOF

摘要

PURPOSE: A self mixing adaptive bias circuit system and a method thereof are provided to improve efficiency by satisfying the allowable linearity condition of an amplifier in a low power region.;CONSTITUTION: A signal sampler(202) generates a sampled output signal by sampling the output signal of an amplifier. A mixer(203) generates a mixed signal by mixing the sampled output signal and the input signal of the amplifier, which has a same carrier frequency as the sampled output signal. A lowpass filter(204) generates an adaptive bias signal by eliminating high frequency component from the mixed signal. A bias feeding block(205) offers the adaptive bias signal to the input of the amplifier. The adaptive bias signal comprises a gate voltage which is received from the input of the amplifier or a base current.;COPYRIGHT KIPO 2010