載波聚合是一項能夠增加系統傳輸頻寬的技術，但載波聚合卻會增加系統的功率峰均值比進而降低系統的效能。在本論文中，我們在系統的傳輸端加入頻域濾波器，濾波器的頻寬隨著旋轉因子的增加而增加，之後再將每個組成載波的相位最佳化。在相位最佳化的計算中，我們使用兩種相位的集合，即{1, i, -1, -i}和{1+i, 1-i, -1+i, -1-i}。計算出所有可能的相位組合，並從中選出一組最佳相位。透過濾波器頻寬的改變與相位最佳化的運算，來降低系統的功率峰均值比。在載波聚合的系統中，我們考慮了一個組成載波到聚合五個組成載波，並透過互補累積分布函數來看功率峰均值比對每種不同聚合方式的影響。我們比較在使用不同的調變模式QPSK，16-QAM，64-QAM，256-QAM，在旋轉因子的範圍從0到1變化時所得之不同的頻域濾波器的頻寬及最佳載波的相位集合下，對於系統的功率峰均值比的影響及對整體系統效能(如錯誤率) 的影響。本論文將最後的模擬結果整理出來並列成表格，當未來當人們使用及設計此系統架構時，可以很快地知道需要將濾波器的旋轉因子值調整到多少，讓系統的功率峰均值比的影響降至最低。

Carrier aggregation (CA) is one the techniques to increase the system bandwidth but with carrier aggregation it increases the peak-to-average power ratio (PAPR) level to worsen the system performance. In this paper we consider to include a spectral filter with roll-off square-root raised cosine structure or to include the same spectral filter cascading with phase randomization in every component carrier (CC) path to improve the PAPR level. In the phase randomization operation, we use two phase sets which are {1, i, -1, -i} and {1+i, 1-i, -1+i, -1-i}. By calculating all possible combinations, the best phase combination has been selected to use in the system to improve the system PAPR level. One to five CCs are considered in the aggregated transmission system the resulting complementary cumulative distribution function (CCDF) PAPR levels and the total system performances (such as the bit error rate) for each possible aggregated system are simulated and compared when QPSK, 16-QAM, 64-QAM, and 256-QAM modulation formats are considered as the roll-off factor of the square-root raised cosine filter varies from 0 to 1 to change the spectrum filter bandwidth and the best phase combination is selected. The simulation results are tabulated that can be used as the design reference when we are considering the selection of the best roll-off factor for the spectral filter to have the best PAPR performance.

目錄
誌謝	I
中文摘要	II
ABSTRACT	III
目錄	V
圖目錄	VII
表目錄	X
第一章 緒論	1
1.1 研究動機與目的	1
1.2 章節介紹	2
第二章 載波聚合系統架構	3
2.1 OFDM系統介紹	3
2.2 功率峰均值比	6
2.2.1 功率峰均值比介紹	6
2.2.2 功率峰均值比定義	7
2.3 單載波分頻多工	10
2.4 載波聚合	13
第三章 系統架構	17
3.1 濾波器	17
3.1.1 濾波器介紹	17
3.1.2 濾波器推導	20
3.2 系統架構一	24
3.3 系統架構二	26
3.4 載波聚合之系統架構	28
3.5 系統架構三	31
3.6 系統模擬結果	34
3.6.1 相鄰式載波聚合模擬	35
3.6.2 對稱式載波聚合模擬	40
3.6.3 模擬結論	46
第四章 接收端架構	49
4.1 載波聚合系統架構一接收	49
4.2 載波聚合系統架構二接收	50
4.3 載波聚合系統架構三接收	52
4.4 BER模擬	53
第五章 結論與未來展望	56
5.1 結論	56
5.2 未來展望	57
參考文獻	58
 
圖目錄
圖 2.1 FDM與OFDM表示圖	4
圖 2.2 整數週期弦波	5
圖 2.3 放大器輸入與輸出示意圖	7
圖 2.4 功率峰均值比與OFDM的子載波關係圖	9
圖 2.5 OFDM與SC-FDMA功率峰均值比比較	10
圖 2.6 OFDM系統架構	11
圖 2.7 SC-FDMA系統架構	11
圖 2.8 子載波映射方式示意圖	12
圖 2.9 CA頻寬示意圖	14
圖 2.10 載波聚合技術概念圖	15
圖 2.11 單載波分頻多工聚合之功率峰均值比關係	16
圖 3.1 不同 之濾波器頻率響應	19
圖 3.2 不同 之濾波器時間響應	19
圖 3.3 系統架構一	24
圖 3.4系統架構二	26
圖 3.5 複製運算	26
圖 3.6 相鄰式聚合	28
圖 3.7對稱式聚合	29
圖 3.8載波聚合系統架構一	30
圖 3.9載波聚合系統架構二	30
圖 3.10載波聚合系統架構三	31
圖 3.11 相位組合示意圖	32
圖 3.12  α=0.1之16-QAM相鄰式三個組成載波	35
圖 3.13  α=0.2之16-QAM相鄰式三個組成載波	36
圖 3.14  α=0.3之16-QAM相鄰式三個組成載波	36
圖 3.15  α=0.4之16-QAM相鄰式三個組成載波	37
圖 3.16  α=0.5之16-QAM相鄰式三個組成載波	37
圖 3.17  α=0.6之16-QAM相鄰式三個組成載波	38
圖 3.18  α=0.7之16-QAM相鄰式三個組成載波	38
圖 3.19  α=0.8之16-QAM相鄰式三個組成載波	39
圖 3.20  α=0.9之16-QAM相鄰式三個組成載波	39
圖 3.21  α=1之16-QAM相鄰式三個組成載波	40
圖 3.22  α=0.1之16-QAM對稱式三個組成載波	41
圖 3.23  α=0.2之16-QAM對稱式三個組成載波	41
圖 3.24  α=0.3之16-QAM對稱式三個組成載波	42
圖 3.25  α=0.4之16-QAM對稱式三個組成載波	42
圖 3.26  α=0.5之16-QAM對稱式三個組成載波	43
圖 3.27  α=0.6之16-QAM對稱式三個組成載波	43
圖 3.28  α=0.7之16-QAM對稱式三個組成載波	44
圖 3.29  α=0.8之16-QAM對稱式三個組成載波	44
圖 3.30  α=0.9之16-QAM對稱式三個組成載波	45
圖 3.31  α=1之16-QAM對稱式三個組成載波	45
圖 3.32 相鄰式聚合頻域示意圖	46
圖 3.33 對稱式聚合頻域示意圖	47
圖 4.1載波聚合系統架構一接收	49
圖 4.2相鄰式聚合	49
圖 4.3載波聚合系統架構二接收	50
圖 4.4 頻譜結合示意圖	51
圖 4.5載波聚合系統架構三接收	52
圖 4.6 不同調變模式與使用最佳 情況下在AWGN通道之系統效能比較圖	54
圖 4.7 不同調變模式與使用最佳 情況下在Rayleigh通道使用ZF等化器之系統效能比較圖	54
圖 4.8不同調變模式與使用最佳 情況下在Rayleigh通道使用MMSE等化器之系統效能比較圖	55

 
表目錄
表 3.1 第三章模擬參數	34
表 3.2 系統功率峰均值比與 變化之關係 	48
表 4.1 第四章模擬參數	53

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