Abstract
Miniature ion thrusters are well suited for future space missions that
require high efficiency, precision thrust, and low contamination in the mN to
sub-mN range. JPL's miniature xenon Ion (MiXI) thruster has demonstrated an
efficient discharge and ion extraction grid assembly using filament cathodes
and the internal conduction (IC) cathode. JPL is currently preparing to incorporate a miniature
hollow cathode for the MiXI discharge. Computational analyses anticipate that an axially
upstream hollow cathode location provides the most favorable performance and beam
profile; however, the hot surfaces of the hollow cathode must be sufficiently downstream
to avoid demagnetization of the cathode magnet at the back of the chamber, which can
significantly reduce discharge performance. MiXI's ion extraction grids are
designed to provide