Directional Sub-THz Antenna-Channel Modelling for Indoor Scenarios

In this paper, sub-THz channel sounding is discussed for indoor scenarios. A directional D-band channel sounder, operational in the full band ranging from 110 to 170 GHz, is presented. We examine the influence of the antenna characteristics on the channel sounder. The channel sounder is used for Line-of-Sight path loss (PL) modelling at sub-THz frequencies for distances up to 4 m. Validation measurements confirm the small beamwidth of the antenna, ranging from 12 degrees for 110 GHz to 11 degrees for 170 GHz. An antenna de-embedding methodology is presented. Fitting Line-of-Sight PL at center frequency 140 GHz to a one-slope model gives a reference PL of 76.0 dB at 1 m and a PL exponent of 1.9. The reference PL is slightly higher than free space PL, whereas the PL exponent is slightly lower.