The Physics and Mathematics of Electromagnetic Wave Propagation in Cellular Wireless Communication

3Mechanism of Wireless Propagation: Physics, Mathematics, and Realization

Summary

This chapter starts with presenting all the various experimental results available in the literature on the propagation path loss for cellular wireless propagation systems. From the experimental data it is quite clear that trees, buildings, and other man made obstacles contribute second order effects to the propagation path loss as the dominant component is the free space propagation of the signal and the effect of the Earth over which the signal is propagating. In addition, the propagation path loss of 30 dB per decade of distance inside a cell is independent of the material parameters of the Earth and this holds even when propagation is over water. This path loss is also independent of frequency. Next it is shown that an electromagnetic macro model can accurately predict the dominant component of the propagation path loss in a cellular wireless communication system which is first 30 dB per decade of distance and later on, usually outside the cell, it is 40 dB per decade of distance between the transmitter and the receiver irrespective of their heights from the ground. This implies that the electric field decays first at a rate of ρ^–1.5 inside the cell and later on, usually outside the cell, as ρ^–2, where ρ stands for the distance between the transmitter and the receiver. It is also illustrated that the so called slow fading is due to the interference between the direct wave and the ground wave ...