The dual polarization antenna with operating frequency range of 170-183 GHz is shown on the picture. Antenna beamwidth is 4.5°. The measured crosspolarization is -37 dB. Input reflection coefficient for both polarization is better than -15 dB.
Overall length of the antenna is ~60 mm with the OMT, and its diameter is 50 mm. The OMT is a cube with 30 mm sides.
A horn lens antenna, such as this one, is very suitable for operations on the ground or on an aircraft.