分散式天線系統(Distributed antenna system)與軟性頻率重用(Soft frequency reuse)為現代最有效地提升系統容量與避免跨細胞干擾的技術。為了獲得這兩種技術的優點，我們設計一個應用在正交分頻多工存取(OFDMA)的新細胞結構，使其結合分散式天線系統與軟性頻率重用。因此，在正交分頻多工存取系統中跨細胞干擾的問題將可減輕同時提供用戶在細胞內的每個角落都能獲得高效能的服務。在多細胞的結構中，我們考慮完整的通道效應；包含路徑衰減、遮蔽效應以及小規模衰減(Small scale fading)並以此數學模型分析系統容量與中斷機率。藉由電腦模擬結果驗證此新細胞結構之效能為最佳並且與數學分析結果相符合。

Nowadays, the distributed antenna system (DAS) and soft frequency reuse (SFR) have been regarded as two effective techniques to boost system capacity and avoid some excess amount of inter-cell interference (ICI). To obtain the both benefits, we build a new cell architecture based on the combination of the DAS and SFR techniques for the orthogonal frequency division multiple access (OFDMA) system. Accordingly, the ICI problem in the OFDMA system can be eliminated and the goal of ubiquitously high data rate services can be achieved. To verify the effectiveness of the proposed cell architecture, the system capacity and outage probability in the multi-cell scenario are derived by taking the complete channel effects into account, including the path loss, shadowing and small scale fading. The simulation results also prove the superior performance of the proposed cell architecture and the exactness of the analytical results.

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