臺灣博碩士論文加值系統

在感知無線電網路中，許多訊號透過合作式中繼點來協助傳輸。先前的直接傳輸在變成二段傳輸之後，能夠在許多情況下提升傳輸率。許多論文中也提到了，最佳化功率分配和合作式中繼點的選擇，希望能夠力求系統最好的傳輸效能。在這篇論文中，我們將改變以往合作式中繼點的選擇方式，嘗試將二段傳輸改為三段傳輸。整個傳輸的過程中，原先只有一次的中繼點選擇，將被改成兩次。我們認為這將會是個不錯的想法，尤其是在第一次選擇到非理想的中繼點情況下。我們以參考文獻中的理論架構和研究方法為基礎，延伸出三段傳輸的系統模型，以及嘗試做兩次中繼點選擇的最佳化功率分配。最後，我們會模擬我們自己定義的三段合作式傳輸，驗證其對於改善系統傳輸效能的可行性。

In cognitive radio networks, many signals use cooperative relay for transmission. Transmission rate of two-hop transmission is better than that of previous direct link transmission. Optimal power allocation and cooperative relay selection in many papers are offered for the best efficiency of transmission. In this thesis, we will change the past way of relay selection, and two-hop transmission will turn into three-hop transmission. Previous selection of once relay will be replaced by selection of twice relay. We claim that it is a good idea, especially when we choose a poor relay at first. Based on theoretic structure and research methods from literature, we derive the system model of three-hop transmission, and we will try to make optimal power allocation of selection of twice relay. Finally, we will show simulation results of three-hop transmission to prove that it can improve efficiency of transmission.

摘要 I
Abstract II
目錄 III
圖表目錄 IV
第一章、緒論 1
第二章、相關研究 3
第三章、合作式中繼點之系統模型 9
3.1 三段傳輸系統模型 9
3.2 合作式中繼點理論架構 13
第四章、中繼點選擇與功率分配 21
4.1 最佳化功率分配 21
4.2 注水原理 24
4.3 演算法與流程圖 30
第五章、模擬結果 33
第六章、結論 41
參考資料 43

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[2] Xiaoxue Liu ; Baoyu Zheng ; Jingwu Cui ; Wei Ji Communication Technology (ICCT), 2010 12th IEEE International Conference on "A new scheme for power allocation in cognitive radio networks based on cooperative relay" Publication Year: 2010, Page(s): 861-864

[3] C Changqing Luo ; Yu, F.R. ; Hong Ji ; Leung, V.C.M.
Communications (ICC), 2010 IEEE International Conference
on ”Distributed Relay Selection and Power Control in Cognitive Radio Networks with Cooperative Transmission” Publication Year: 2010 , Page(s): 1- 5

[4] Liying Li ; Xiangwei Zhou ; Hongbing Xu ; Li, G.Y. ; Dandan Wang ; Soong, A. Wireless Communications, IEEE Transactions on "Simplified Relay Selection and Power Allocation in Cooperative Cognitive Radio Systems" Publication Year: 2011, Page(s): 33-36

[5] Chengshi Zhao ; Kyungsup Kwak Communications Letters, IEEE "Joint sensing time and power allocation in cooperatively cognitive networks" Publication Year: 2010 , Page(s): 163-165

[6] Xiangwei Zhou ; Jun Ma ; Li, G.Y. ; Young Hoon Kwon ; Soong, A.C.K. Communications, IEEE Transactions on "Probability-based combination for cooperative spectrum sensing" Publication Year: 2010 , Page(s): 463-466