Development and Environmental Evaluation of a 1-W-class Dielectric Resonator Oscillator for a Microwave-discharge Ion Thruster on Satellites

A microwave-discharge ion thruster utilizing water-vapor for satellites is being developed due to the advantages in safety, cost-effectiveness, and size improvements compared to other thrusters. The thruster system consists of an oscillator-stage, driver-amplifier-stage, final-amplifier-stage, and a microwave-discharge ion thruster. To realize the advantages of a water-vapor based system, we developed a dielectric resonator oscillator (DRO) with a 10-W-class GaN power transistor. The oscillator has to induce 1 W output as the driver-amplifier-stage requires 1 W (30 dBm) input to operate at the most optimal power efficiency. In this report, we explain the development of the DRO which is a 32.6 dBm output at 4.2501 GHz, and detail the environmental evaluations complied with space standard from the SMC-S-016.