TABLE OF CONTENTS In this chapter the wireless propagation phenomenon between the transmitting antenna(s) and the receiving antenna(s) will be presented. The model derived is commonly called the wireless multipath channel model.
First additive white Gaussian noise (AWGN) is presented due to its simple elegance and ability to support closed form expressions and mathematical tractability. Rayleigh fading is discussed along with its companion, Rician multipath fading. Next the wireless channel bandwidth is introduced thus starting a discussion on frequency selective fading (FSF). These natural forms of interference are complimented with the system-made forms of interference such as adjacent channel interference (ACI) and co-channel interference (CCI).
Taking a more macroscopic view of the wireless channel model will lead to describing how the separation between the transmitter and receiver, called path loss or signal attenuation, affects the received signal power.
As discussed in Chap. 1, complex envelope theory was introduced with a few purposes in mind, one being efficient computer simulation. With this comes a presentation of a few simulation models to emulate the multipath fading phenomenon.
Lastly, the time varying nature of the wireless channel bandwidth (BW) is discussed by means of the birth (or creation) and death (or deletion) of multipaths being received. As a means of a demonstration vehicle, an application to DS-CDMA is given in terms of the implications of this time variation to the performance of the RAKE receiver.
This first section will introduce additive interference in the form of white Gaussian noise (WGN).
