A Hall effect thruster is an electric propulsion device used for station keeping and attitude control of satellites. The operating principle of this kind of thruster consists of heating a gas mixture by means of a high temperature arc discharge. The heated propellant is then ejected through a nozzle to produce thrust.
One important issue which arises in the actual spacecraft integration of this kind of technology is the environmental impact of the Hall effect thruster’s plume, especially on microwave communication systems.
The thruster produces a weakly ionized plasma, which modifies the free space normally surrounding the satellite and causes phase shift, attenuation, phase modulation and amplitude modulation of the microwave signals to and from the spacecraft. This is a primary user concern that must be addressed quantitatively before the Hall effect thrusters technology can be fully integrated aboard a spacecraft.
The purpose of the plasma module integrated in ADF is just that of providing a modeling capability able to give space system integrators a guide to follow when considering antenna - plasma plume interaction.
The plasma model here addressed, has been developed around a widely accepted theoretical model of the arc jet plume. The basic model has also been improved to include a temporal and spatial wave caused by discharge instabilities of the thruster
The module accepts the following input data:
- Characteristics and geometry of the plasma plume emitted by ion thrusters;
- Geometry of the spacecraft;
- Position and orientation of the ion thrusters mounted on the satellite.
Typical outputs of the analysis are:
- Antenna pattern distortions;
- Frequency modulation effects.
Plasma plume module allows the optimisation of antenna placement and orientation and the selection of the best possible ion thrusters in order to minimise or eventually eliminate their unwanted interactions and maximize the efficiency of the link between the antennas mounted on the satellite and the ground stations