IMT-Advanced 시스템용 GaN MMIC Doherty 전력증폭기의 구현

In this paper, we investigate a proper structure of power amplifier for IMT-Advanced system. The power amplifier must have high efficiency and minimized circuit size. The Doherty power amplifier was designed and implemented for next generation mobile communication base station using GaN MMIC (Monolithic Microwave Integrated Circuit). The experiment results satisfied the specification of amplifier. The gain was 22.2 dB and the PAE(Power Added Efficiency) was 38 %. The ACPR (Adjacent Channel Power Ratio) was below -35.37 dBc at 2,655 MHz. Especially, the proposed power amplifier had 34 % efficiency at 37 dBm and it improved efficiency maximum 15 % than class AB structure.