Human Body Shadowing at 28 GHz

It is well known that human body shadowing is a significant propagation effect in indoor communications especially at frequencies higher than 10 GHz. Thus, in this work, human body shadowing in directive short range channel is measured at 28 GHz. A distance of 10 m between the transmitting antenna and the receiving one is used in the measurement campaign. Two body orientations are used in this study. Four persons have participated in the measurement campaign as objects. Shadowing results are given for single person case and two person case. It is shown that maximum body shadowing occurs when the body is near to the transmitting or receiving antenna. Minimum shadowing occurs at almost the half of the distance between the transmitting and receiving antennas. It is shown that, body shadowing loss is low when the body is not in the center line between the transmitting and receiving antennas. At an antenna height of 1.2 m and 1.4 m, height and weight of the person under study affect the shadowing loss. In general, higher person and heavier person give a rise to higher shadowing loss. Crossing the line between the transmitting antenna and the receiving one, body shadowing loss of 10–36 dB is noticed. For the first orientation, shadowing loss due to two persons reaches to 36.5 dB when one of them moving along the line between the transmitting antenna and the receiving one and the other is at 5 ms from the transmitting antenna. A shadowing loss of 50.1 dB is observed when the third person is at 9.5 m from the transmitting antenna a d the fourth one is at 0.5 m from the transmitting antenna.