2.44GHz室內無線電空-時通道特性之量測與研究

Abstract

本研究利用向量通道脈衝響應量測系統(RUSK Channel Sounder)於交通大學光復校區室內環境下將環境分為三類進行2.44GHz無線電空-時通道脈衝響應定點量測。藉由定點之『功率角度極座標分佈圖』探討多重路徑空-時分佈與量測環境的關係，並經由多重路徑之TOA與AOA統計分析發現TOA的機率密度可用『指數衰減函數』表示其分佈，而AOA的分佈則呈現數個(通常不大於三個)主要叢集特性，各叢集之主要指向與傳播環境及發射端和接收端相對位置有關。於是本論文提出叢集式機率密度函數描述AOA之分佈，另外根據分析TOA與AOA的聯合機率密度發現多重路徑在時間與空間上相關性並不明顯。最後統計空-時通道之特性參數如： (mean excess delay)、 (delay spread)、 (angular spread)、 (angular constriction)、 (maximum fading angle)，用以描述室內無線傳播通道在空間及時間上之特性，並做為設計室內無線通信系統的參考數據。

In this thesis, an advanced channel sounder was employed to perform the spatio-temporal radio channel characteristics measurement in NCTU indoor environment. The relation between multipath components in spatio-temporal domain and measurement site is discussed with power angle profiles. It is found that the probability density of arrival can be described by an exponential decaying function and the distribution of angle of arrival can be grouped to several main cluster where the number of cluster is site dependent. Then a clustered probability density function is proposed to describe the distribution of angle of arrival where several spatio-temporal channel parameters are applied, which includes (mean excess delay)、 (delay spread)、 (angular spread)、 (angular constriction)、 (maximum fading angle). Characteristics of these parameters are discussed and studied also.