| Summary: | 碩士 === 國立交通大學 === 電信工程系 === 89 === This thesis presents a hybrid spatio-temporal model to predict TOA、AOA and signal strength of microcellular radio channel in urban environment. First, it is found that delay spread and angle spread decrease gradually with the increase of propagation distance. The ranges of delay spread and angle spread are 20ns~70ns and 2°~20°, respectively. Second, the hybrid model combines a deterministic model with a statistical model. The former model that is a site-specific model can calculate direct wave, ground-reflected wave and the field scattered from the street walls. The latter one employs statistical approach to calculate the scattered fields due to randomly positioned scatterers along the streets, which includes vehicles, pedestrians, trees, lampposts, motorcycles and et al. A spatio-temporal channel measurement using a high performance radio channel sounder helps us to develop the statistical model. It is found that number of randomly positioned scatterers (N) is equal to 10, which is a reasonable value for both sites #1 and site #2 and seem to be irrelevant the street width. We validate the hybrid model by comparing the computed result with measured ones. It is found that the hybrid model is reasonably accurate.
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