Evaluation of Attenuation by Tree in 300-GHz-band Wireless Communications

We evaluated attenuation by trees in the 300 GHz band. Received power was measured twice, once when there were leaves and once when there were no leaves, at the same propagation path. The measurement results indicate that the average attenuation by trees is 21 dB in the presence of leaves and it is 15.8 dB in the absence of leaves. The variability of attenuation by trees was 14 dB greater with leaves than without leaves. These results indicate that the average and variability of attenuation by tree were greater when leaves were present.