Far-field antenna characterization in the sub-THz region based on electrooptic near-field measurements

This paper describes an antenna characterization system in the sub-THz region that is based on photonic self-heterodyne and nonpolarimetric techniques. This system shows a stable measurement, with the signal-to-noise ratio of 30 dB and the phase standard deviation of 81×10^-3 rad. Far-field horn antenna characterization at 125 GHz is demonstrated. We confirm that the radiation patterns calculated from the near-field measurements are in good agreement with the simulated results.