Reflector Antennas Based on Flexible Ceramic and Glass Substrates

Abstract

Metallized glass and ceramic substrates have a strong potential for use in aerospace applications due to their light weight, durability, flexibility, and environmental stability. Epoxy-less bonding between metal and dielectric is strongly preferred in space to avoid material degradation due to outgassing. A novel laser welding process was developed to directly attach 10–50 µm metal foil to a 200–700 µm thick glass or 40–140 µm thick alumina substrate. Mechanical and environmental tests showed that a very strong metal-dielectric bond can be formed, capable of sustaining harsh environmental conditions. The proposed method can therefore significantly improve reliability and lifetime of spacecraft components that require bonding of dissimilar materials. High flexibility and mechanical strength of ceramics and ion-exchanged glasses allow for their application as substrates of mechanically reconfigurable parabolic reflector antennas. To facilitate the reflector design and optimize its performance, mechanical analysis was carried out to identify the appropriate thicknesses and mechanical reliability criteria of the substrates. Prototypes of a parabolic cylinder reflector antenna and a corner cube retroreflector were fabricated and characterized in an anechoic chamber at millimeter wave frequencies (26.5-40 GHz).