Microcell propagation model for network planning

A new ray-tracing propagation model for network planning purposes is investigated. The accuracy of the model is verified by measurements in the center of Helsinki in Finland covering different transmitter and receiver locations as well as different propagation situations. The model is designed for situations where the transmitting and receiving antennas are below the rooftops and it uses a vector formatted building database as the input. Multiple reflections from the building walls and single and double diffractions from building wedges are computed. Multiple reflections followed by one or two diffractions can also be taken into account. New geometrical algorithms have been employed in the search of multiple reflected and diffracted rays to decrease the computation time applicable for network planning applications. Computation times of the coverage calculation are shown for different map data and for different propagation contributions