Measurement and analysis of the scattering properties of cement surfaces of urban environment in the millimeter waveband

The use of the low-frequency scattering coefficient leads to inaccurate receiving-power predictions in the millimeter-wave band. The inaccurate signal will hinder optimization of the base station location. In the millimeter waveband, a building surface becomes rougher in an urban environment. The scattering becomes increasingly significant and a non-negligible factor. In this article, the scattering characteristics of rough cement wall surfaces are studied to improve the scattering coefficients for millimeter waveband communications. The ray tracing method is adopted, and the lambertian and directive models are incorporated into this method, respectively. Moreover, the signal distributions of rough cement wall surfaces are acquired through an outdoor experiment at different incidence angles. The results reveal that the scatterings that are embedded into ray tracing are better than those which were not considered in the ray tracing, compared with the experiment. The directive model agrees more with the measurements than the lambertian model. The scattering coefficient S and exponent alpha(R) of the directive model are 0.19 and 1 in the millimeter waveband, respectively, which disagree with the results at low frequencies. The scattering properties can be applied to simulate signal propagation in urban environments to improve the reliability of mobile telecommunication systems.