Gallium nitride has attracted a great deal of interest in recent years due to its power handling ability. In addition, its noise performance is known to be good. In this letter, we present a method for determining the bias current density needed to obtain optimal noise figure for gallium nitride high-electron mobility transistors (HEMTs). Particle swarm optimization is used to fit transistor S parameters to a model, enabling the calculation of the transistor's two-port noise parameters. This process is performed for different bias points for different-sized transistors, leading to the conclusion that a current density of 0.3 mA/μm yields the best minimum noise figure.

gallium nitride, low noise amplifiers, MMIC, noise figure, noise modeling
Microwave and Optical Technology Letters

Ross, T. (Tyler), Cormier, G. (Gabriel), Hettak, K. (Khelifa), & Amaya, R. (2011). Particle swarm optimization in the determination of the optimal bias current for noise performance of gallium nitride HEMTs. Microwave and Optical Technology Letters, 53(3), 652–656. doi:10.1002/mop.25758