Path Loss Measurement of Outdoor Wireless Channel in D-band.

D-band (110-170 GHz) has received much attention in recent years due to its larger bandwidth. However, analyzing the loss characteristics of the wireless channel is very complicated at the millimeter-wave (MMW) band. Research on D-band wireless channels has been focused on indoor short-distance transmissions, with few studies looking at outdoor long-distance wireless channels. In this paper, we provide the design of the D-band outdoor long-distance transmission system, propose the outdoor line-of-sight (LOS) propagation measurements, and study the outdoor D-band propagation loss characteristics with distances up to 800 m. The path loss model uses the Floating Intercept (FI) and the Close-In (CI) model is established based on the least square method. In the CI model, the path loss exponent is greater than 2 and increases with frequency, while in the FI model, the path loss exponent has no apparent frequency dependence. The results show that D-band path loss in long-distance outdoor scenarios is greater than that in free space, indicating that the propagation condition is worse than in free space. The results show that both models have similar performance. Under this basis, the model with the smallest number of parameters would be the optimal choice. In addition, these results prospectively provide a theoretical model for designing and optimizing high frequency mm-wave propagation measurements at a distance of 200 m and beyond.