Numerical synthesis of tri‐reflector CATR with high cross‐polarisation isolation

In this Letter, a tri‐reflector compact antenna test range (CATR) with a paraboloidal main reflector and two shaped sub‐reflectors is synthesised by the kinematic and dynamic ray tracing method, while the high cross‐polarisation isolation is achieved through the proposed system geometry. Numerical simulations by general responsibility assignment software patterns demonstrate that a cross‐polarisation isolation >40 dB and a peak‐to‐peak amplitude (phase) ripple <1 dB (10°) can be achieved on the principal cuts of the designed quiet zone at 90–325 GHz. This clearly shows that the high cross‐polarisation isolation in such a tri‐reflector CATR can be achieved by the proposed antenna geometry without depolarisation control in the shaping procedure.