Integrated Design Tools for RF Antennas for Helicon Plasma Thrusters

Abstract

In this communication we report on a combined experimental-numerical activity that was conducted to assess the antenna-plasma interaction within a Helicon plasma source for space thrusters. The experiment is based on a versatile, re-configurable set-up which allows testing multiple thruster configurations under different operating conditions, featuring a high-efficiency RF antenna. The numerical results were obtained by means of various simulation tools for both RF circuit and antenna-plasma interface analysis; these tools were validated against experimental data. The results helped to improve our understanding of antenna-plasma coupling and the assessment/prediction of the RF system performance. Nomenclature RF= Radio Frequency HPT = Helicon Plasma Thruster RPA = Retarding Potential Analyzer IEDF = Ion Energy Distribution Function DAQ = Data AcQuisiton Pp = Active power coupled to the plasma Zp = Plasma impedance Rp = Plasma resistance Xp = Plasma reactance ηa = Antenna efficiency _______________________________________________________________________________________