Concentric Split Ring Resonator as a Plasma Source in Miniature Ion Thruster

Abstract

In this study, the concentric split ring resonators (CSRRs) were explored as a potential plasma source for miniature ion thrusters. The CSRRs were operated at 11 W on average while the thruster beam voltage and the mass flow rate varied. The testing of different CSRR designs showed that an increase in the number of rings decreases plasma generation, and reducing the width of the inner ring increases the plasma generation. The thruster properties with different designs showed a similar trend. The beam current was measured by sweeping a Faraday probe across the thruster. The maximum thrust measured among all designs from the thruster was $243~\mu $ N for a mass flow rate of $1.63\times 10^{-4}$ g/s and anode voltage of 575 V. The maximum thruster efficiency in terms of specific impulse was 152 s and 1.5% in terms of thrust-to-input-power efficiency.