Tests of a 1.5-M Reflector Antenna in a 650 GHz Hologram CATR

MilliLab/Radio Laboratory at the Helsinki University of Technology (TKK) is developing a hologram-based compact antenna test range (CATR) for high gain antenna testing at millimetre and sub-millimetre wavelengths. The capabilities of the hologram CATR were demonstrated in an antenna test campaign, where the ADMIRALS RTO was tested at the frequency of 650 GHz. The binary amplitude hologram used as the collimator has a diameter of 3.16 m. The quiet-zone width was 2 m and height 2.3 m. In this paper, the construction of the hologram CATR is presented. Also, some results of the quiet-zone field verification and the antenna tests are presented. Stretching of the hologram substrate and its effect on the quiet-zone field are studied.