NLOS Path Loss Model for Low-Height Antenna Links in High-Rise Urban Street Grid Environments

摘要

This paper presents a NLOS (non-line-of-sight) path loss model for low-height antenna links inrectangular street grids to account for typical D2D (device-to-device) communication link situations inhigh-rise urban outdoor environments. From wideband propagation channel measurements collected inSeoul City at 3.7 GHz, we observed distinctive power delay profile behaviors between 1-Turn and 2-TurnNLOS links: the 2-Turn NLOS has a wider delay spread. This can be explained by employing the idea thatthe 2-Turn NLOS has multiple propagation paths along the various street roads from TX to RX, whereasthe 1-Turn NLOS has a single dominant propagation path from TX to RX. Considering this, we developa path loss model encompassing 1-Turn and 2-Turn NLOS links with separate scattering and diffractionparameters for the first and the second corners, based on the Uniform Geometrical Theory of Diffraction. In addition, we consider the effect of building heights on path loss by incorporating an adjustable“waveguide effect” parameter; that is, higher building alleys provide better propagation environments. Whencompared with field measurements, the predictions are in agreement.