Radio propagation characteristics in underground streets crowded with pedestrians

Radio propagation characteristics in an underground street crowded with pedestrians are presented. Measurements were carried out on vertical and horizontal polarization characteristics in a frequency range from 250 MHz to 12.4 GHz. In the analysis, the region with pedestrians is modeled as a lossy, homogeneous dielectric slab. Based on the method of effective dielectric constant, some numerical results are presented for the attenuation constant and for the field distribution in the cross section and are compared with experimental data. It is shown that the method is applicable in determining the propagation characteristics in underground streets crowded with pedestrians