Reflectivity of Antenna Reflectors at Frequency Range 110 - 350 GHZ

Accurate theoretical electromagnetic calculation and prediction of reflection loss for precisely described high reflective multi-layer configurations is possible but not easy. Surface roughness can be comparable to skin depth thickness at millimetre wavelength. Modelling results are often only indicative and initial guiding. Testing is required. Availability and implementation of an accurate testing technique with a fraction of a 1/100 dB resolution capability and "promille type" accuracy (depending on samples to be tested) is very important. It is clear, that reflection loss testing for high performing reflector antennas is mandatory. The paper outlines state of art and gives examples of interesting reflection loss tests of state-of-art metallised composite samples.