Effect of arcjet plume on satellite reflector performance

The effect of an arcjet plume on the performance of onboard reflector antennas is studied. The arcjet plume is modeled as an inhomogeneous scatterer with a smoothly varying refractive index. The spatial distribution of the refractive index is related to the measured electron density data based on the cold plasma model. Since the plume size of interest is more than several wavelengths in extent, geometrical optics is used to calculate the microwave propagation through the plume. The trajectory, phase, amplitude, and polarization of the high-frequency ray field transmitted through the plume are numerically computed based on the laws of geometrical optics. Once the ray optics field transmitted through the plume on the near-field aperture is found, the far-field pattern of the antenna can be calculated by a ray-tube integration scheme. Results obtained with the proposed method are presented.<>