GaN HEMT high efficiency power amplifiers for 4G/5G mobile communication base stations

In this paper, the key technology development on the base station power amplifiers (PA) for 4^th generation (4G) and 5^th generation (5G) of mobile communication systems is discussed. In considering the major requirements from 4G/5G systems of the spectrum extension, smaller size and lower power consumption, GaN HEMT device is the most promising technology because of its potential of broad band and high power density based on its wide band gap properties and the proven ability to realize the energy efficient amplifiers. The paper tries to provide the future requirements and expectation on GaN or the wide band gap compound semiconductor devices assuming its applications for the latest amplifier technologies which are the advanced Doherty PA, the Outphasing/Linear-amplification-using-Nonlinear-Components (LINC) PA and the switch-mode PA with the achieved performances and perspectives.