Simulations of high linearity and high efficiency of class B power amplifiers in GaN HEMT technology

We describe the design and simulation of highly linear and highly efficient common source class B power amplifiers. Efficient broadband class B push-pull amplifiers are not feasible at microwave frequencies as baluns with desired broadband even-mode impedance are unavailable. We find, however, that a single-ended class B amplifier with bandpass filtering has an equivalent efficiency and linearity. Simulations of class B designs predict a power added efficiency (PAE) of 48% with 40 dBc of third order intermodulation product (IMD3) performance when biased close to the pinch-off voltage.