Nonlinear Modelling of RF GaN Devices and Utilization in RF Power Amplifiers for 4G Applications

Abstract

This paper studies the large signal modeling of Gallium Nitride (GaN) High Electron Mobility Transistor (HEMT) and optimizes a nonlinear model of GaN HEMT that takes into account both small and large signal behavior based on Angelov model. The performance of the optimized model is verified with a selected GaN HEMT (TriQuint TGF2023-01) and compared to GaAs HEMT (NEC 900175) and an early study fabricating GaN Hetero-junction Bipolar Transistor (HBT) through DC characteristics, S- parameter simulations, cut-off frequency, output gain, minimum noise figure, and stability. Finally, the optimized GaN HEMT model is validated through utilizing it in an RF power amplifier design for 4G applications. It achieves double efficiency and 7dB enhancement in the maximum output power when compared to GaAs HEMT conventional design. In addition, the adjacent channel power ratio is increased by (15-20) dBc which makes the transmission mask deeply complies with the WiMax standard.