Assessing the contribution of multiply scattered radio waves to the impulse response of a wireless channel

Using a three-dimensional topographic map of a typical microdistrict in Kazan, multipath radio wave propagation in mobile radio communication systems was modeled by the method of ray tracing. An ensemble of 4000 radio links, each 200 m long, was generated and randomly positioned on the map. The wave propagation scenarios included both line-of-sight and non-line-of-sight conditions of visibility between transmitters and receivers. A quantitative analysis of the contribution made by multiply scattered waves to the channel impulse response was performed. The results show that single-scattering approximation is generally sufficient for 200-m line-of-sight links. However, in the non-line-of-sight scenario, it is necessary to also account for waves scattered two or three times.