Lateral, full-3D and vertical plane propagation in microcells and small cells

When the height of the transmitter is close to building heights, over-rooftop contributions, i.e. full-3D rays or rays in the vertical plane, become relevant in propagation. Full-3D propagation, vertical plane propagation and lateral propagation are compared, both mutually and against measurements in Munich (Germany) and Rosslyn (VA, USA). To perform our study we made use of a full-3D ray tracing tool. In addition, a deterministic vertical plane prediction model was implemented based on a literature review of published models. In Munich, which has a regular mixture of building heights with virtually no high rise buildings, our deterministic vertical plane model was found to be accurate in predicting the average measured power for receivers far from the transmitter. Deterministic models require, in general, less calibration with measurements than empirical models. The wedge representation of buildings in the vertical plane was found to give better agreement with measurements than the classical knife-edge representation