Measurements of high gain antennas at millimeter wavelengths using a hologram CATR

A compact antenna test range (CATR) has great potential for testing electrically large antennas. However, the application of conventional reflector type CATRs becomes increasingly difficult, though not impossible, above 100 GHz due to the tight surface accuracy requirements for the reflectors. A CATR based on a planar hologram has been studied to overcome the problems incurred by the use of reflectors with insufficient surface accuracy. This paper summarises the results obtained for a hologram CATR at Helsinki University of Technology.