Abstract: The modeling of wireless channels vary greatly in different propagation environments. For example, the line-of-sight (LoS) radio links and non-line-of-sight (NLoS) are two basic channel models in wireless communications, but they are totally different from each other. For a LoS channel, if the signals propagate in an additive white Gaussian noise (AWGN) environment, it is referred to as an AWGN channel. However, the AWGN channel is seldom available for wireless systems in urban areas. For a mobile wireless system inside a city, since there are many structures between the base station and the mobile station, the signals are transmitted in NLoS channels with strong influence from diffractions and scatterers (Stuber, 2001). Thus, the received signal may arrive from many different directions and different delays. This phenomenon is referred to as multipath propagation. The multipath signals may be constructive or destructive and thus many fading models are proposed to represent it, such as Rayleigh fading and Rician fading. Rician fading is observed when, in addition to multipath signals, a direct path between the transmitter and the receiver exists.
Publication Year: 2008
Publication Date: 2008-07-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot