近年，多輸入多輸出 (Multiple Input Multiple Output，簡稱MIMO) 技術開啟全球下一代通訊的競爭熱潮。因為在有限的頻寬下，MIMO技術是可以有效提高傳輸容量的手段，故手機放置天線數量在未來會必然的增加，而工業界也正努力朝著 MIMO智慧型手機發展，可預期的是在未來，多天線的智慧型手機將會是手機的性能指標。
本論文主旨是基於 LTE MIMO下行鏈路結構，並搭配使用國家儀器 (National Instruments，簡稱NI) 所開發的實驗室虛擬儀器工程平台 (Laboratory Virtual Instrumentation Engineering Workbench，簡稱LabVIEW) 作為基礎。在硬體開發上，我們已完成一套可達實時空中下載技術的LTE 傳輸系統，最終可將星座圖解回用戶資料。此外，我們在接收端部分利用軟/硬體做結合，目的是將未來更具有發展潛力的新型演算法套用在此平台上做效能測試，而這些測試包括：通道估測、MIMO 檢測器及錯誤更正碼。最終，我們能夠透過該量測平台輔助手機開發商，更快速評估出天線和演算法在實際通道上的效能，利於導入市場的速度。

This thesis suggests some technical research on the future development of communication, based on the LTE downlink architecture and MIMO system model. We use the radio platform of NI LabVIEW FPGA with MIMO system as a basis for development of hardware and software. Part of hardware has been able to complete all the entire real-time communication system architecture. In addition, in order to verify the effectiveness of the software on the actual channel, we use the combination of soft-hardware to develop some software testing in high complexity, such as channel estimation, MIMO detector, and error correction code. In the future, we can quickly test the performance on OTA by the software design, and achieve the program to hardware step by step to bring more practicality.
In addition, we build an antenna measurement platform based on the R&S instrument, in which we develop a way to obtain the impulse response of the real multipath channels. This technology also can be applied to reduce the time that OTA measurement usually waste, because the obtained impulse responses used to simulate the received signal for platform testing. We also implement the convolutional code and turbo code based on the LTE standard in the system platform. With these error correcting codes, we can keep a low error rate, and make the spectrum as close as possible to the channel capacity.

第一章 緒論 1
1.1 引言以及動機 1
1.2目標和論文安排 3
第二章 LTE系統與相關技術簡介 4
2.1 OFDMA調變 4
2.2 LTE多工模式介紹 5
2.3 FDD下行鏈路系統的訊框架構 6
2.4 時槽結構與實體資源單元 7
2.5 循環前綴 8
2.6 主要同步訊號 9
2.7 參考訊號 10
第三章 LTE為架構的平台和通道估測相關技術 12
3.1 系統相關參數 12
3.2 系統硬體架構 13
3.2.1 發送端硬體架構 15
3.2.2 接收端硬體架構 16
3.3 發送端程式設計 16
3.4 接收端程式設計 18
3.5 軟/硬體結合架構 19
3.5.1 通道資訊矩陣作法 22
3.5.2 接收資料作法 23
3.6 實際測量結果 24
第四章 通道估測演算法之衍生應用 26
4.1 窗口選擇與通道估測影響之模擬 26
4.2 還原時域上通道效應和模擬效能 28
4.3 判斷路徑流程圖 30
4.5 實測結果 32
4.6 應用及未來發展 32
第五章 平台加入編碼後效能比較 34
5.1 迴旋碼 34
5.1.1 非遞迴迴旋編碼 34
5.1.2 遞迴迴旋編碼 35
5.1.3 刺穿碼 35
5.1.4 BCJR解碼 36
5.1.5 8X4系統使用迴旋碼不同碼率比較 36
5.2 渦輪碼 37
5.2.1 格子圖解碼收斂法 39
5.2.2 交錯器 39
5.2.3 不同碼率的渦輪碼 40
5.2.4 循環冗餘校驗 41
5.2.5 渦輪碼解碼器 42
5.2.6 8X4系統使用渦輪碼不同碼率比較 43
第六章 總結 45
附錄 47
參考文獻 49

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