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.