The Precise Microwave Resonator Spectroscopy of Gases and Condensed Media

In this paper, it was shown that reflectivity of reflector surfaces depends on the quality of thin metal reflecting layers and their coating. The influence is of course relatively larger for high reflective metals because of the smaller skin-depth. Results presented in this paper show low reflection loss for Planck reflector technology and very reasonable reflection losses for a metalized carbon fiber reinforced plastic (CFRP) technology. The latter technology has been measured at low temperature (liquid N₂) and it is of interest to observe more than an expected factor ´2´ reduction in reflection loss. The importance of measurement of reflection loss has been discussed and the results presented or referred to in this paper confirm such a need.