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This paper reports the modelling of CCP‐RF discharges (13.56 MHz) in pure nitrogen, produced within a cylindrical parallel‐plate reactor, similar to a GEC reference cell surrounded by a lateral grounded grid, at 0.1–2 mbar pressures and 10–50 W coupled powers. This study is a first step in simulating Titan’s chemistry at laboratory scale, using the PAMPRE experiment. Modelling results are compared with experimental measurements of the average electron density, and the self‐bias potential at the polarized electrode.

The antenna design proposed here is based on the resonant double loop concept with conjugate T matching to make the circuit resilient to strong plasma load variations as ELMs. The antenna is constituted of two main parts; the in‐vessel launcher which is inside the primary torus vacuum and the Compact Vacuum Tuners (CVT) that is located after the first barrier in a private vacuum. This CVT allows to match at the strap location, the antenna impedance with the plasma load, over the 45 to 55 MHz frequency range. It has been designed to ease its repair and maintenance, and can be easily removed from the rear without breaking the primary vacuum. Apart from the Faradays screens fit to shape the plasma edge, the in‐vessel launcher and CVT are made out of 6 identical modules, to allow the best economical approach for the manufacture, the assembly and the maintenance of the antenna.

In recent years electromagnetic (RF) plasma generation and acceleration concepts for plasma-based propulsion systems have received growing interest, inasmuch as they can yield continuous thrust as well as highly controllable and wide-ranging exhaust velocities. The acceleration units mostly adopt the Ion Cyclotron Resonance Frequency (ICRF)—a proven technology in fusion experiments for transferring large RF powers into magnetized plasmas, and also used by the VASIMR propulsion system. In this work we propose and demonstrate the use of TOPICA code to design and optimize the ICRF antenna of a typical acceleration stage. To this end, TOPICA was extended to cope with magnetized cylindrically-symmetric radially-inhomogeneous warm plasmas, which required coding a new module charged with solving Maxwell’s equations within the plasma to obtain the relevant Green’s function ~Y(m;kz) in the Fourier domain, i.e. the relation between the transverse magnetic and electric fields at the air-plasma interface. Then, calculating the antenna input impedance—and hence the loading—relies on an integral-equation formulation and subsequent finite-element weighted-residual solution scheme for the self-consistent evaluation of the current density distribution on the conducting bodies and at the air-plasma interface.