Estimation and measurement of cylindrical wave propagation in parallel plate with honeycomb spacer for the use in mm-wave RLSA

Analysis of non-metallic honeycomb structures to be used as the waveguide at 32 GHz in a satellite on-board Radial Line Slot Antenna (RLSA) was carried out. Incorporating honeycomb structure for the waveguide is indispensable to meet the requirements for space-use while maintaining the electrical characteristics. At 8.4 GHz this was successfully done using Quartz honeycomb structure, where the cell size was much smaller than the guided wavelength. At 32 GHz, with the design frequency 4 times larger, estimation of propagation characteristics in the millimeter wave region was a necessity. Simulation results anticipated anisotropic propagation around 32 GHz for larger cell sizes and significant material loss for smaller cell sizes. These results were partly confirmed by measurements of honeycomb structure and antenna measurements supported significant material loss.