在正交分頻多工系統中，如何消除跨細胞干擾問題以提昇傳輸率為一項重要的研究議題。近年來，規劃新的頻譜配置結構與提出有效率之中繼策略成為兩大解決方向。在本文中，我們結合上述兩個概念，建構出一個具有高傳輸率之細胞架構。首先，我們將細胞分為內圍和外圍區域，分別給予2/3及1/3頻帶資源，以有效消除跨細胞干擾問題。其中，內圍區域配置較多頻帶資源，以確保基地台與中繼器之間的傳輸品質，加強中繼器的使用效率。再者，利用空時編碼實踐多樣性增益，配合低功率的中繼器可減少跨細胞干擾個數。不同以往，我們考慮完整通道特性來分析多細胞環境下之效能表現，其中包括路徑耗損，具有對數常態分布特性之遮蔽效應與衰弱反應。我們提出的細胞架構在傳輸率與中斷機率上佔有極大優勢，本文並針對傳輸率與中斷機率進行推導分析，結果顯示，此分析方法與模擬結果幾近吻合。

In the orthogonal frequency division multiple access (OFDMA) system, how to eliminate the inter cell interference (ICI) problem is the key to providing ubiquitously high data rate services. In the recent years, the novel frequency allocation scheme (FAS) and effcient relay strategy has become two popular techniques to solve this problem. In this thesis, we combine these two techniques to build a high-capacity cell architecture.
Firstly, each of the inner and outer zone areas within a sector is allocated a portion of bandwidth, i.e. 2/3 and 1/3, respectively, so as to effectively eliminate the ICI problem. Secondly, a wider bandwidth for the inner zone areas is allocated such that the higher link capacity along the path from base station (BS) to relay station (RS) can not be a bottleneck during the relay procedures. Thirdly, the Alamouti coded relay strategy can own the diversity gain; and the lower transmission power of RS can further reduce the amount of ICI. Fourthly, different from the literature, the complete channel effects including the path loss, log-normal shadowing and the fading, are taken into considerations of performance analysis in the multiple cell environments. The advantages of the proposed cell architecture are verified via simulation and analytical results in terms of capacity and outage probability.

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