An experimental and theoretical study of some aspects concerning the performance of a millimetrewave compact antenna test range

Compact antenna test range (CATR) reflectors intended for operation well within the millimetre wave bands are often made up of individual accurately fabricated panels. This results in an interpanel gap. This discontinuity in the reflector´s surface will result in a degradation of the range´s performance. A practical method proposed to cure such a problem is to cover the gaps by a thin conductive tape. Although by careful practice one can restore the conductive properties of the reflector´s surface it must be recognised that the existence of the tape itself is a perturbation of the surface accuracy. The effects will be most severe in the millimetre wave frequencies. The associated problems are investigated experimentally, and theoretically. Antenna pattern measurements are described based on the testing of a 200 mm, 90° offset reflector operating at 183 GHz