本篇論文提出一個在覆蓋式感知網路下功率分配策略，其中每一個傳送端或接收端都配置一根天線。由於每個節點都只配置一根天線，吾人於次使用者採用疊加編碼方式藉以實現覆蓋式感知傳輸，並於疊加編碼設計功率配置機制。我們首先分析主要使用者和次要使用者之位元錯誤率。其後，在滿足主要使用者與次要使用者的位元錯誤率下，設計最小功率分配策略。由於此最佳化設計並非凸優化，欲求出最佳解是有困難的。因此我們針對主要使用者和次要使用者提出兩個可行的位元錯誤率近似式，進而將原先優化問題轉成凸優化，故可利用現行數值方法求其最佳解。模擬結果驗證了所提出的功率配置設計可應用在不同通道環境。

In this thesis, we propose a power allocation strategy for overlay cognitive networks, where each node is equipped with single antenna. Owing to the overly strategy, the secondary user (SU) can help transmit the primary user’s (PU) data and meanwhile conveys its own data with the superposition coding (SC). We first analyze the bit-error-rate (BER) for the PU and the SU. Then, the power allocation strategy is devised by minimizing total power, providing that the BER of the PU and that of SU are guaranteed. Since the BER formulations are not convex, the optimization is difficult to conduct. We then propose two new tractable BER approximations for the PU and the SU, which can sophisticatedly transfer the design into a convex problem. The optimum solution can thus be easily obtained. Simulations verify our power allocation design is validated for different channel environments.

論文審定書………………………………………………………………..……………..i
誌謝………………………………………………………………..…………………….ii
中文摘要………………………………………………………………..………………iii
英文摘要……………………………………………………………………...………...iv
目錄……………………………………………………………….……………………..v
圖次……………………………………………………………….…………………….vi
表次……………………………………………..……………………………………vii
第1章 序言……………………………………………………………………………..1
第2章 系統模型………………………………………………………..……………....6
第2.1節 覆蓋式傳收機架構……………..…………………………...………..……6
第2.2節 主要使用者接收端效能…………………..………….......……...………...8
第2.3節 次要使用者接收端效能…………………..………….......……...……….10
第3章 最小功率配置傳收機設計……………...……………………..…..…………13
第3.1節 最佳化問題描述………………………………………………………….13
第3.2節 最佳化問題近似………………………………….………………………13
第4章 系統模擬及探討………………………………………………………………18
第5章 結論與未來展望………………………………………………………………24
附錄A…………………………………………………………………………………..25
附錄B…………………………………………………………………………………..30
參考文獻……………………………………………………………………………….32

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