Experimental Assessment of Human Blockage at sub-THz and mmWave Frequency Bands

Abstract

The fifth generation (5G) of mobile communications relies on extremely high data transmission rates utilizing a wide range of frequency bands, including FR1 (sub-6 GHz) and FR2 (mmWave). Future mobile communications systems are envisaged to operate at the electromagnetic spectrum beyond FR2, above 100 GHz, known as sub-THz band. These new frequencies open up challenging scenarios where communications will have to rely on a major contribution such as the line-of-sight (LoS) component. To the best of the authors' knowledge, for the first time in the literature this work studies the human blockage effects over an extremely wide frequency band from 75 GHz to 215 GHz considering: (i) the distance between the blocker and the antennas and (ii) the body size and orientation. The obtained results are fitted to modifications of the classical path loss models and compared to 3GPP alternatives. The average attenuation increases from 42 dB to 56 dB when frequency rises from 75 GHz to 215 GHz. On the other hand, an 18 dB increment in the received power is observed when the Tx--Rx separation is increased from 1 m to 2.5 m. Finally, variations of up to 4.6 dB are found depending on the blocker's orientation.