在本論文中，我們針對使用正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)技術的無線通訊系統，在手持式數位影像廣播系統(Digital Video Broadcasting - Handheld, DVB-H)和IEEE 802.16d微波存取全球互通系統(World Interoperability for Micro-wave Access, WiMAX)上做通道估測演算法效能的電腦模擬，並且把演算法用硬體實現。
在DVB-H的部份，由於DVB-H應用於手持式接收裝置上，必須要能夠在高速移動下保持良好的通訊，因此通道環境變化較快，接收機的訊號品質也面臨較嚴苛的考驗。在本論文中，我們利用決定回授(Decision Feedback)的方法達到效能的改善，並使用Verilog硬體描述語言(Hardware Description Language, HDL)作硬體設計。最後，再配合時間同步、頻率偏移估測、分散式領航信號偵測等基頻訊號處理，整合成一個完整的無線通訊基頻接收機，並向國家積體電路中心申請0.18um製程下線。
在WiMAX的部份，由於IEEE 802.16d主要用於固定式的無線通訊，因此通道變化較為緩慢，因此我們便沒有採用決定回授的方法來進行通道估測，以簡化電路設計的複雜度。演算法的效能經過電腦模擬後，我們以Verilog撰寫硬體描述語言，並使用Synplify做電路合成，最後並把程式下載到現場可程式化閘陣列(Field Programmable Gate Array, FPGA)，以邏輯分析儀驗證電路設計的正確性。

In this thesis, we investigate and implement the channel estimation schemes for digital video broadcasting - handheld (DVB-H) and IEEE 802.16d world interoperability for micro-wave access (WiMAX). Both systems are based on the orthogonal frequency division multiplexing (OFDM) technique. The performance of the channel estimation schemes is first verified by using simulation experiments. Then, the channel estimation algorithms are realized by hardware implementation.
For the DVB-H systems, since the mobile device may have a relatively high speed, the channel condition is time-varying, leading to serious degradation in channel estimation. In this thesis, the decision feedback mechanism is adopted to improve the performance of the channel estimation. The adopted structure for channel estimation is realized by using Verilog hardware description language (HDL). Then, all the baseband signal processing related algorithms, which include timing synchronization, frequency offset estimation/compensation, and scattered pilot detection, are integrated together using 0.18 ASIC process.
For the IEEE 802.16d WiMAX, since it is dedicated for fixed wireless applications, the channel condition is basically stationary and easier to obtain. Therefore, the decision feedback mechanism is not adopted to save hardware complexity. The system performance is verified by conducting simulation experiments. The adopted channel estimation algorithm is implemented by using Verilog HDL. Finally, the whole baseband receiver is realized by using the field programmable gate array (FPGA) and verified by using the Agilent logic analyzer.

第一章 導論 1
1.1 背景與研究動機 1
1.2 論文架構 2
第二章 DVB-H 傳送端實體層標準簡介 3
2.1 通道編碼與調變 5
2.1.1 多路傳輸調適與隨機式能量分散 5
2.1.2 外部編碼與外部交錯 6
2.1.3 內部編碼 7
2.1.4 內部交錯 8
2.1.4.1 位元交錯 9
2.1.4.2 符號交錯器 11
2.1.4.3 深度交錯 12
2.1.5 訊號星座圖與映射 13
2.1.6 OFDM碼框結構 14
2.2 可獲取資訊的參考訊號 17
2.3 參照序列 18
2.3.1 分散式領航訊號位置 18
2.3.2 連續性領航訊號位置 19
2.3.3 領航訊號所載數值 20
2.3.4 傳輸參數訊號 20
2.4 TPS的調變方式 20
2.4.1 TPS傳輸數值對照 21
2.4.2 同步字元 22
2.4.2.1 訊號位元使用個數 22
2.4.2.2 碼框編號 22
2.4.2.3 星座圖 23
2.4.2.4 等級結構資訊 23
2.4.2.5 碼率 23
2.4.2.6 保護區間 24
2.4.2.7 傳輸模式 24
2.4.2.8 細胞基地台識別 24
2.4.2.9 DVB-H特有機制資訊 25
2.4.2.10 TPS的錯誤偵測 25
第三章 常見的通道估測演算法 26
3.1 一維線性內插 26
3.2 預設性一維線性內插 27
3.3 二維線性內插 28
第四章 WiMAX 傳送端實體層標準簡介 29
4.1 外傳送機 29
4.2 內傳送機 30
第五章 DVB-H通道估測模擬與實作 33
5.1 測試的通道環境 33
5.2 不同通道環境下的模擬與規範 34
5.3 在具都卜勒效應時變通道下的模擬 37
5.3.1 RA6 Channel 38
5.3.2 TU6 Channel 40
5.4 回授通道估測 42
5.5 通道估測實作 46
第六章 WiMAX 通道估測模擬與實作 48
6.1 WiMAX 通道估測硬體架構 48
6.2 Synplify 合成與FPGA 平台測試 49
第七章 結論 52
參考文獻 53

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