A linearization method with optimizing impedance of envelope signal to suppress IMD3 of RF CMOS power amplifier

Abstract

In this paper, the linearization method with optimization of the impedance of the envelope signal of a RF CMOS power amplifier is proposed. By analyzing the extended Taylor series, it was determined that the IMD3, gain, and output power of the CMOS power amplifier could be regulated using the impedance of the envelope signal. To evaluate the feasibility of the proposed method, we designed a 1.9-GHz CMOS power amplifier using a 110-nm RFCMOS process. Using the proposed method, the measured IMD3 is suppressed and consequently, the measured linear output power is also improved by 3.7 dB. The measured results confirm the feasibility of the presented approach.