Tuning Ray Tracing for Mm‐wave Coverage Prediction in Outdoor Urban Scenarios

Propagation characteristics at 26 GHz, 28 GHz and 38 GHz (Ka band) in outdoor en18 vironments are analyzed through path loss measurements in two different urban scenarios and used to tune a Ray Tracing model, with specific focus on non-specular scattering and vegetation attenuation. The contribution from non-specular components in non line-of-sight conditions is shown to be much more important than expected even for narrowband prediction, differently to what was found in previous studies at lower frequencies. Attenuation through vegetation is also very important and can be described using vegetation polygons and a simple linear attenuation model. When these effects are modeled inside the Ray Tracing tool, prediction accuracy is good. However, scattering from vehicles and other cluttering objects is shown to give a relevant contribution in deep non line-of-sight locations, and further work is needed to systematically model such effects into the ray tracing engine