Antenna optimization for helicon plasma thrusters

he helicon plasma thruster (HPT) is an advanced electric propulsion system based on the propagation of helicon waves in a plasma confined by an external magnetic field. Its electrodeless-free design enables a theoretically longer lifetime compared to more conventional electric thrusters. The HPT consists of three main components: an RF an-tenna that ionizes the propellant by coupling electromagnetic power, an ionization chamber that contains a high-density magnetized plasma, and a magnetic nozzle that converts elec-tron thermal energy into directed ion kinetic energy, generating thrust. Despite many years of development, achieving good thrust efficiency remains a significant challenge, making antenna optimization one of the main goals for performance improvement.