臺灣博碩士論文加值系統

本論文針對OFDM系統之時序同步問題，提出Constant Pilot Padding Method(CPPM)。CPPM方法為在傳送端頻域上，有規則的安插調變資料，於時域產生具備重複特性的時域符元，作為時序估測使用之Preamble符元，並以頻域上填補的Pilot符元，提供通道估測能力，同時可於Preamble符元內傳送部份資料。另分析頻域上填補的Pilot值，對於時序估測效能及時域符元的PAPR值影響。最後以LOS及NLOS環境的室外實測通道，使用建議的Pilot值，分別檢測CPPM方法的時序同步及通道估測效能。模擬結果顯示，CPPM時序估測誤差，明顯小於S&C方法，且有與Park’s方法相當的估測效能，CPPM方法可同時進行通道估測，Park’s方法則不具此功能。

In this paper, we propose a Constant Pilot Padding Method (CPPM) that can perform both the timing synchronization and channel estimation in the Orthogonal Frequency Division Multiplexing (OFDM) systems. The CPPM method exploits the repetitive structure of the preamble that can be generated by inserting the constant pilots in the frequency domain to execute the timing synchronization. In addition, the CPPM method has the ability of channel estimation with these padding pilots.
Compared with the conventional synchronization methods, such as the S&C method and the Park’s method, the preamble of the CPPM provides not only timing synchronization but also data transmission. Simulation results show that the proposed timing estimation performance is more precise and robust than the S&C method and the Park’s method.

目錄
摘要 I
Abstract II
目錄 III
圖目錄 V
表目錄 IX
第一章 導論 1
1.1背景簡介 1
1.2論文大綱 2
第二章 Proposed OFDM System於時序估測及通道估測之效能 3
2.1 三種時序估測法及其效能分析 5
2.1.1 S&C Method時序估測法[1] 6
2.1.2 Minn’s Method時序估測法[2] 11
2.1.3 Park’s Method時序估測法[3] 13
2.1.4模擬結果及比較 15
2.2 Proposed Symbol Timing Estimation 19
2.2.1 Constant Pilot Padding Method (CPPM) 19
2.2.2於不同調變模式之時域符元格式 21
2.2.3 Proposed時序估測法模擬及比較 33
2.3 通道估測法與效能分析 46
2.3.1Proposed通道估測法 47
2.3.2於Rayleigh Fading Channel之模擬結果 49
第三章 Padding Value對PAPR及時序估測效能之影響 54
3.1 Padding Value對PAPR值之影響 54
3.2 Padding Value對時序估測效能的影響 56
3.2.1於QPSK調變，改變P值檢視時序估測效能 57
3.2.2於16QAM調變，改變P值檢視時序估測效能 62
3.2.3於BPSK調變，改變P值檢視時序估測效能 64
第四章 於室外量測通道之效能分析 70
4.1室外量測通道介紹 70
4.2 Proposed時序估測法於室外量測通道之模擬 75
4.2.1以QPSK調變於室外量測通道之模擬結果 76
4.3通道估測法於室外實測通道之模擬 79
4.3.1於室外實測通道之模擬結果 79
第五章 結論與未來工作 84
5.1結論 84
5.2未來探研方向 85
參考文獻 87

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