Measurement bench

ESA’s  (Sub)mm-wave RF Characterization test facility is a quasi-optical free-space RF measurement bench. The properties of test materials is characterized by a single pass through the sample or single reflection on the sample, in transmission and reflection configuration, respectively. In transmission configuration, the field radiated by the transmit horn is collimated by an elliptical mirror and after passing through the sample, it is refocused by a second elliptical mirror to the receive antenna. The transmission performance of the sample is determined by the ratio between the transmission measurement with and without sample. In reflection configuration, the reflectivity is measured via separated transmit and receive ports. The calibration of this set-up requires a high accuracy reflection standard to be placed at the sample position making all subsequent measurements relative to this standard. The reflection standard used is a high purity grade copper sample, machined with high precision diamond cutting, surface roughness 50 nm rms.