本論文中，我們重新研究了細胞網路架構的頻率分配方案（FAS)，而且是考慮了使用者非均勻分布的情形。由於細胞中，扇形區域間的使用者分布不均勻，所以整體網路架構的交通流量變得非常不平衡。為了滿足使用者的要求，所以就提出了用戶導向之動態頻率配置方案（Duo-FAS），使得子載波的個數可以依據使用者在扇形區域中的數量來分配。不過，此方案的技術卻移除了頻率配置（例如：傳統三扇形的細胞架構）原本可以避免干擾的好處。這意味著使用此方案會產生出額外的細胞間相互干擾（ICI）。幸運的是，多輸入多輸出（MIMO）網路技術可以有效解決細胞間相互干擾的衝擊。使用此方案，多輸入多輸出網路中合作的細胞數量與對象，會跟傳統的方案大有差別。因此，適當挑選合作對象就變成一個重要的議題。關鍵在於：位於細胞邊緣的使用者有較高的優先權，能夠適當挑選相鄰的細胞，以形成合作的多輸入多輸出網路群體，使得細胞間的強干擾可以消除。模擬結果證明了細胞的消息容量（capacity）有所提升。

In this thesis, we revisit the frequency allocation scheme (FAS) for the cellular networks by taking the non-uniform distribution of users into account. Owing to the non-uniformly distributed user density from sector to sector, the traffic loads become highly unbalanced across whole network. Thus, to satisfy users' requests, the dynamic user-oriented FAS (Duo-FAS) is proposed to allocate different amount of subcarriers to sectors according to the variant user densities. However, the Duo-FAS technique can partially remove the innate benefit of interference avoidance via frequency planning, i.e. the conventional three-sectored cell architecture. That means some extra inter-cell interference (ICI) can be produced by using Duo-FAS. Fortunately, the so-called network multiple-input and multiple-output (MIMO) technique can effectively alleviate the impact of ICI. Thanks to Duo-FAS, the number and positions of the cooperative cells of network MIMO can be significantly different from the conventional schemes. Thus, properly selecting the cooperative cells becomes a pivotal issue. The key is that a user near the cell edge has a higher priority to adaptively select the neighboring cells to form a cooperative network MIMO group so that the strong ICI can be eliminated. Via the simulation results, the superior performance in the aspect of cell capacity is proved.

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