A GaN HF-band Power Amplifier using Class-D Topology for Jupiter Ice Penetrating Radar

We present the design and measured results of a class-D GaN HF-band power amplifier for use in an ice penetrating radar bound for Jupiter's icy moons of Ganymede, Callisto and Europa. The design uses a novel digital driver square-wave generator to achieve high-efficiency. The power amplifier generates >46.7 dBm of RF output power at >82 % drain efficiency. The frequency and time domain variation of a 3 MHz bandwidth pulsed chirp signal was <0.5 dB. In addition, the amplifier was designed to meet the harsh Jovian environment with a 10 year plus mission life.