Development and characterization of the ALFVEN thruster

Abstract The Advanced Linear Field Vector Excitation Network (ALFVEN) thruster represents a novel RF plasma propulsion system developed to enhance the coupling efficiency of electromagnetic waves to plasma, particularly in low-power conditions. This study presents the design, development, and experimental characterization of the ALFVEN- 4050, an RF thruster utilizing a resonant network to generate a linear-polarized electromagnetic field in the transverse direction of the thruster's discharge chamber. The innovations of ALFVEN- 4050 include utilizing a square-loop antenna array and the orthogonal coupling of the transverse electromagnetic field and uniform magnetic flux across the discharge chamber, enabling efficient plasma generation. Experimental results using argon and krypton propellants demonstrate promising ignition capabilities for low gas flow rate and stable impedance matching. The ALFVEN thruster's performance highlights its potential to overcome challenges in low-power RF plasma thrusters, such as low mass utilization efficiency, paving the way for advanced EP concepts for applications with alternative propellants.