在正交分頻多工系統(Orthogonal Frequency Division Multiplexing, OFDM)中，盲式估測可以獲得較高的頻譜使用效益。在盲式資料偵測系統中，因為傳送的訊號中沒有領航訊號加在其中，因此接收端做資料偵測時，有資料模糊性(Ambiguity)的問題，目前解決資料模糊性的方法大致可分為三種：加入領航訊號(Pilot Signal)、使用疊加序列(Superimposed Training)、或是利用通道編碼(Channel Coding)，而本論文為了能夠達到完全地盲式估測，在此我們將以通道編碼的方式來解決資料模糊性。在既有文獻中已有人針對低密度奇偶校驗編碼(Low-Density Parity-Check Codes, LDPC)，提出在BPSK調變下可避免模糊性的編碼方式。而在本篇論文中，我們考慮更為泛用的線性區塊編碼(Linear Block Code, LBC)，並將其推廣至其他常見的高階調變，包括QPSK，16QAM，以及64QAM，在調變技術符合格雷編碼的前提下，我們歸納出產生模糊性的內積變化量，並進一步推導產生不具模糊性之線性區塊編碼的充份條件，只要線性區塊編碼符合該條件，便可確保其碼字不具模糊性，以達到完全盲式估測的目的。最後，在模擬的章節中，我們將分別針對不具模糊性與具有模糊性的線性區塊編碼進行資料估測，為了公平起見，具有模糊性的編碼會再搭配領航訊號，以解決模糊性的問題，由模擬結果可以看出，兩種編碼方式在高訊號雜訊比(Signal to Noise Ratio, SNR)的情況下具有相當接近的效能，換言之，只要採用適當的通道編碼，其符合我們所提出來充份條件，便可在效能幾乎無損的情況下，更進一步地提高頻譜使用效率。

In orthogonal frequency division multiplexing (OFDM) system, blind estimator was proposed which can obtain high bandwidth efficiently. There is a serious ambiguity problem in blind data detector structure. Solution methods can divide into three cases: pilot signal, superimposed training, and channel coding. In order to achieve totally blind estimate, we use channel coding to solve ambiguity in this thesis. In previous study, it had been use low-density-parity-check code (LDPC) to solve ambiguity, and proposed an encoding method to avoid ambiguity for BPSK. However, we consider generic linear block code (LBC) and want to extend BPSK modulation to higher modulation scheme, including QPSK, 16QAM, and 64QAM. For any constellation follows grey coding, we induct a difference of inner product for ambiguity and derive some sufficient conditions for LBC. If LBC satisfy some conditions, then it could avoid ambiguity between valid code words and it can achieve totally blind estimate. In simulation section, for data estimate, we respectively use two LBC cases, which exist ambiguity or not. In order to be fair, we insert a pilot to solve ambiguity in LBC, which exist ambiguity. In simulation results, the performance of two cases is similar in high signal to noise ratio (SNR). In other words, if we use proper channel code which it satisfy sufficient conditions, then we can increase bandwidth efficiently.

致謝 I
論文鑑定書 II
中文摘要 IIII
Abstract IV
目錄 V
圖目錄 VII
第 一 章 導論 1
1.1 研究動機 1
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
第 三 章 傳統盲式資料偵測架構 8
第 四 章 不具有資料模糊性的通道編碼 11
4.1 格雷碼的特性 11
4.2 符合格雷碼特性的調變機制與提出的定理 12
4.3 利用通道編碼解決資料模糊性 18
4.3.1 利用LDPC解決BPSK資料模糊性 18
4.3.2 利用LBC解決高階層調變資料模糊性 19
4.3.2.1 整數倍的調變位元向量定理 20
4.3.2.2 非整數倍的調變位元向量定理 21
4.3.2.3 如何設計出所有碼字都滿足各自內積取2的餘數皆為0或1 24
4.4 基於推導的理論而提出新的架構圖 25
第 五 章 模擬結果 28
第 六 章 結論 36
參考文獻 37
中英對照表 41
縮寫 45

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