TABLE OF CONTENTS The detailed knowledge of radio propagation characteristics is essential to develop a successful wireless system. Measurement studies have been carried out to identify propagation loss, spatial distribution of power, wideband and narrowband statistics concerning the random variables of received signals at a fixed location due to any surrounding movement, and delay spread. A radio channel is a generally hostile medium in nature. Transmitted signals undergo several propagation phenomena such as reflection, diffraction, and scattering before they reach the receiver. This is mainly caused by the existence of objects in the physical channel between a transmitter and a receiver such as buildings, trees, mountains, hills, and moving objects. Therefore it is rather difficult to predict the channel behavior. Traditionally, radio channels are modeled in a statistical way using real propagation measurement data. Classical propagation models, commonly used for narrowband transmission systems, represent a signal in the radio environment using a large-scale path loss component together with a medium-scale slow varying component having a lognormal distribution, and a small-scale fast varying component with a Rician or Rayleigh distribution, depending on the presence or absence of the line-of-sight (LOS) component between the transmitter and receiver [1, 2]. Accordingly, conventional radio propagation models describing a wireless cellular environment have focused on:
Area mean power depending on the path loss characteristics between the transmitter and receiver.
Local mean power within that area, which is slow varying. This can be represented by a lognormal distribution.
Superimposed fast fading instantaneous power, which...
