在我們的研究裡，我們使用單載波(Signal Carrier)系統並結合與類正交空時區塊編碼(Quasi-Orthogonal Space-Time Block Code, QOSTBC)相似的類正交空頻區塊編碼(Quasi-Orthogonal Space-Frequency Block Code, QOSFBC)用於四根傳送天線上。在上傳通訊時，這種需要多根傳送天線的編碼會因為行動通訊設備的大小及複雜度而受到限制，所以在我們的研究裡，使用了合作式通訊(Cooperative Communication)來解決這個問題。在我們提出的架構中，我們在來源端(Source Node)使用兩根天線，並在中繼端(Relay Node)使用一根天線來完成QOSFBC所需要被達到的四根天線的空間多樣性(Spatial Diversity)。我們提出的架構特別適合用於上傳傳輸。除此之外，因為QOSFBC及QOSTBC在部分非對角項元素上有非零值，所以沒辦法達到全散度(Full Diversity)的特性。在我們這個研究內，我們提出一種在中繼端將混合訊號做相位旋轉的方法，讓QOSFBC(QOSTBC)的散度提升，並能提升位元錯誤率(Bit Error Rate, BER)的效能。此外，因為單載波系統使用於空頻區塊編碼(Space Frequency Block Code, SFBC)或是QOSFBC時，因為置換了子載波(Subcarrier)的順序，進而導致低峰均值功率比(Peak-to-Average Power Ratio, PAPR)的特性被破壞，為了解決這個問題，我們也提出了一種更正型的SFBC編碼，其能提供較低的PAPR。在我們所提出的分散式QOSFBC架構中，可以在來源端提供一個較低的PAPR並使用鄰近的子載波做編碼。因此即使在頻率選擇性衰落的通道(Frequency Selective Fading Channel)環境，我們提出的方法也可以提供一個不錯的BER效能。我們將以模擬結果驗證我們提出的架構能夠提供不錯的PAPR效能及BER效能。

In this study, single carrier system with quasi-orthogonal space-frequency block code (QOSFBC) for four transmit antennas are considered, which is similar to the well-known quasi-orthogonal space-time block code (QOSTBC). Employing multiple antennas in uplink communications is restricted, due to the limitation of size and complexity of the mobile equipment. The cooperative communication can overcome these problems. In our proposed scheme, only two transmit antennas are used in the source node and the relay node uses one antenna to complete the QOSFBC, which are needed to achieve four antennas spatial diversity. This new scheme is especially suitable for uplink transmissions. In addition, since QOSFBC and QOSTBC have nonzero values in the non-diagonal elements, QOSFBC cannot achieve full diversity. In this study, we also propose a phase rotation method in the relay node to improve the diversity and the bit error rate (BER) performance. Moreover, single carrier system with space frequency block code (SFBC) and QOSFBC scheme permute the spectral components of the transmitted signal and destroy the low peak-to-average power ratio (PAPR) property. In order to solve this problem, we proposed a modified SFBC coding to decrease the PAPR. The proposed distributed QOSFBC scheme can provide a lower PAPR in the source node and use the adjacent subcarriers simultaneously. Thus, the proposed method provides good BER performance over frequency selective fading channel. The PAPR and BER performances are shown through simulations.

誌謝 ii
中文摘要 iii
Abstract iv
目錄 v
圖次 vii
第一章 導論 1
1.1 研究背景 2
1.2 研究動機 3
1.3 論文架構 4
第二章 系統介紹 5
2.1 SC-FDE 5
2.2 SC-FDMA 6
2.3 合作式通訊網路 7
2.4 空時及空頻區塊編碼 9
2.4.1 正交空時區塊編碼 9
2.4.2 類正交空時區塊編碼 11
2.4.3 空頻區塊編碼 14
2.4.4 分散式空時及空頻區塊編碼 17
第三章 提出架構 19
3.1 來源端 19
3.2 中繼端 22
3.2.1 中繼端未知通道狀態資訊 22
3.2.2 中繼端已知通道狀態資訊 26
3.3 目的端 30
3.3.1 中繼端未知通道狀態資訊 30
3.3.2 中繼端已知通道狀態資訊 36
第四章 Modified SFBC coding 42
4.1 SFBC關係式推導及PAPR模擬 42
4.2 4Tx關係式推導及模擬 46
4.3 提出的Modified SFBC coding方法 58
第五章 模擬結果 63
5.1 提出的Modified SFBC coding BER 63
5.1.1 使用SC-FDE的BER 63
5.1.2 使用SC-FDMA的BER 63
5.2 提出的合作式QOSFBC BER 65
第六章 結論 70
參考文獻 71
中英對照表 78
縮寫對照表 83

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