Radiation Pattern Measurements of Corrugated Horn Antenna for 175 GHz CTS Diagnostics at Wendelstein 7-X

The study of the emission properties of the 140 GHz corrugated horn antenna in the frequency range 170–174 GHz has been presented and discussed. This extended frequency range is a part of upgrade of the collective Thomson scattering (CTS) diagnostic at Wendelstein 7-X stellarator. The antenna characterization was done using the raster scan method and thermographic measurements with the help of 175 GHz Clinotron oscillator. The experimental results showed the possibility of the antenna application for the new CTS detector in the both frequency ranges at 140 GHz and 174 GHz.