High temperature RF transmission tests on EM windows conducted at the French solar furnace

The band transmission data of electromagnetic antenna window materials exposed to heat fluxes of magnitude 200 cal/cm² s to 400 cal/cm^.2s are presented. The measurements were performed at the solar furnace of the Centre National de la Recherche Scientifique, Odeillo, France. The purpose of the tests was to analyze material performance under a very high pulsed heat flux radiant energy environment. The high-purity ceramic materials that are light in color showed very little RF attenuation during the test runs because of their excellent reflective properties to the focused radiant energy. All samples tested were exposed to the heat flux environment until the exposed surface underwent melting.