在分散式傳送天線系統架構下，不同的傳送端具有各自的載波頻率偏移，因此在接收端的混合訊號中，會存在多個不同載波頻率偏移所產生的干擾。為了能夠有效對抗多個載波頻率偏移所造成的干擾，本篇論文提出了一個干擾自我消除的方法。在我們提出的架構之中，兩個不同的中繼站分別使用不同的載波來傳送訊號，並且在接收端結合中繼站所傳來的訊號，實現載波間干擾的自我消除。
另一方面，為了能讓系統達到較好的效能，在接收端時域所接收到的訊號，會進行粗略地載波頻率偏移補償，傳統的做法是補償各個頻率偏移量的中間值。補償中間值雖然是一個簡單的做法，但是並不能使系統效能達到最佳化，因此本篇論文的另一個重點，便是基於最大化平均訊號對干擾能量比的準則，由理論推導出最佳載波頻率偏移補償值，此最佳補償值與通道狀況以及各自的載波頻率偏移有關。
最後，我們也透過模擬驗證，我們所提出的架構在相對載波頻率偏移不超過0.3時，能夠有效的降低位元錯誤率；我們也經由電腦模擬，比較補償載波頻率偏移之中間值以及最佳值對於系統效能的差異。

In this thesis, we investigate a wireless communications system with distributed transmit antennas. Under such system scenario, the received signal has multiple carrier frequency offsets (CFOs) since each transmitter has its own oscillator, leading to serious inter-carrier interference (ICI) at the receiver end. Therefore, an ICI self-cancellation scheme is proposed in this thesis, where two different relay nodes use different sub-carriers. When the signals from different relay nodes are combined at the destination node, the ICI self-cancellation can be achieved.
In addition, the quality of the received signal can be further improved if the residual CFO can be properly compensated. Traditionally, the medium value of the various CFOs is taken for compensation because of its simplicity. However, a medium value does not result in the optimal performance. In this thesis, a close form expression of optimal CFO is derived to maximize the average signal to interference power ratio. It is shown that the optimal CFO compensation is a function of channel state and individual CFOs.
Simulation experiments are conducted to investigate the performance of the proposed scheme. It is shown that the system bit error rate can be substantially improved when the CFO is less than 0.3 subcarrier spacing.

致謝 .................................................................................................................................. I
中文摘要 .......................................................................................................................... II
Abstract ............................................................................................................................ III
目錄 ............................................................................................................................... IV
圖目錄 ............................................................................................................................ VI
第 一 章 導論............................................................................................................ 1
1.1 研究動機 ........................................................................................................ 2
1.2 論文架構 ........................................................................................................ 3
第 二 章 正交分頻多工系統 ................................................................................... 4
2.1 正交分頻多工系統架構 ................................................................................ 4
2.2 分散式多傳單收系統架構 ............................................................................ 7
第 三 章 傳統載波間干擾自我消除之架構 ......................................................... 10
3.1 單一天線載波間干擾自我消除之架構 ...................................................... 10
3.2 既有的分散式天線載波間干擾自我消除之架構 ...................................... 12
第 四 章 既有的求解最佳補償載波頻率偏移量 ................................................. 18
第 五 章 多重載波間干擾自我消除之技術 ......................................................... 20
5.1 多重載波間干擾消除之調變方式 .............................................................. 20
5.2 平均訊號對干擾功率之比值 ...................................................................... 21
5.3 平均載波間干擾功率的上限邊界 .............................................................. 23
5.4 求解最佳補償載波頻率偏移量 .................................................................. 29
第 六 章 模擬結果 ................................................................................................. 32
第 七 章 結論.......................................................................................................... 42
參考文獻 ......................................................................................................................... 43
中英對照表 ..................................................................................................................... 46
縮寫 ................................................................................................................................ 49

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