CDMA/TDD 系統的主要優點是它藉由分配上下傳通道的數目提供非對稱的流量需求。各細胞使用相同頻帶，因此不同細胞間時槽分配的差異會讓系統遭受嚴重的多用戶干擾。多細胞系統結合方向性天線，在無線資源的分配上提供了額外的自由度並可提高系統的容量。
　　在本篇論文中對於各細胞間不同的傳輸要求提供了正確的干擾分析。由分析的結果，提出一個合適的時槽分配方法以避免相鄰細胞時槽之間的相互干擾，並提高無線資源使用效率。另外我們以軟體模擬來印證數學分析結果。

　　The key advantage of CDMA/TDD system is to accommodate asymmetric traffic by allocating number of uplink and downlink channels. Because both uplink and downlink use the same frequency band in each cell, the different time slot allocation between each cell will causes severe multiusers' interference in the TDD system. If we combine cellular system with directional antenna technique, the directivity of directional antennas can provide an additional degree of freedom for allocating radio resource and improve the system capacity.
　　In this thesis, we provide exact analysis of interference (include the MS-MS, BS-BS and MS-BS interference) according to the different traffic patterns between adjacent cells. From the analytic results, we propose a proper time slot allocation scheme to avoid the multiusers' interference between time slots from neighboring cells and increase the utilization of the radio resource. Then the analytic results are verified by simulation.

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