| Summary: | 碩士 === 國立交通大學 === 電信工程研究所 === 84 === In our research, a 3-dimension ray-tracing technique is used
to predict the receiving pwer on the street and establish the
effective reflection surface for the walls beside the street. A
statistical method is developed to establish average field
strength empirical model and fading model for UHF radio
propagate along a street in urban area , the random distribution
of thereceiving power can be computed by these two model. we can
predict the path loss along differentstreet by ray-tracing
technique and image method,the difference of the parameters for
these two model is investigated when the transmitter and the
movingpath of receiving are changed. It is found that there is
quite different when the moving path of receiver is changed for
the parameters of empirical formula on similar streets. It is
considered to be line-of-sight propagation on thestreet, the
small-scale fading envelopedistribution is Rician. It is found
that no regular rule to describe the change of Rician factor
when the moving path of reciever is along a street, but the
Rician factor is descreated with the propagation path is
increatedwhen the moving path of recirver is across a street.
|
|---|
