Antenna Design Method for Low Power Miniaturized Microwave Discharge Ion Engines

Abstract

In this study, we succeeded to develop a very low power miniaturized ion engine powered by microwave discharge. The accomplished performance was ion production cost of 240W/A and propellant utilization efficiency of 39% by input microwave power 1.0W and mass flow rate of 0.15sccm. In order to realize this very low power operation, we have proposed an antenna design method for miniaturized microwave ion engines. The effectiveness of this method was verified by plasma observation inside the discharge chamber and ion beam extraction characteristics of the engine. Based on this method, antenna of the engine was designed and improved. As a result we have achieved to our goal.