Efficient AlGaN/GaN Linear and Digital-Switch-Mode Power Amplifiers for Operation at 2 GHz

This work addresses the enormous efficiency and linearity potential of optimized AlGaN/GaN high-electron mobility transistors (HEMT) in conventional Doherty linear base-station amplifiers at 2.7 GHz. Supported by physical device simulation, the work further elaborates on the use of AlGaN/GaN HEMTs in high-speed current-switch-mode classD (CMCD)/class-S MMICs for data rates of up to 8 Gbit/s equivalent to 2 GHz RF-operation. The device needs for switch-mode operation are derived and verified by MMIC results in class-S and class-D operation. To the authors’ knowledge, this is the first time 2 GHz-equivalent digital-switchmode RF-operation is demonstrated with GaN HEMTs with high efficiency. key words: Gallium Nitride, power amplifier, switch-mode, efficiency