Effect of Gap between Arm and Torso and Clothing on Human Body Shadowing at 300 GHz

We assessed the human body shadowing at 300 GHz using a human body phantom and terahertz hemispheric scanner. Measurements were taken at chest and belly levels to change the gap between arm and torso. When the gap between the torso and arm was 20 mm, the shadowing loss was approximately 5 dB higher than when the gap between the torso and arm was 45 mm. At chest height, the shadowing loss with down coat was approximately 5 dB lower than that without clothing. The measurement of the direction-of-arrival (DOA) of radio signals in the 300 GHz band shows that the clothing spreads the DOA of diffracted waves at human body in the elevation direction.