在合作式通訊系統中，藉由中繼站的輔助能夠有效提升系統效能。將無線獵能技術應用在合作式通訊系統中，能讓中繼站自行充電並且提供轉傳資訊所需能量以降低更換電池或充電所需成本，但獵能技術每次所能獵取的能量有限且較為微弱，因此如何有效累積電量及分配各個中繼站在每次傳輸所扮演的角色是一重要問題。在此篇論文中，我們提出一種適用於中繼站具有有限電量及封包儲存空間且能進行獵能充電的中繼站選擇機制。在同時考慮通道狀態資訊與電量及封包儲存狀態下，進行中繼站之行為分配，選擇出最佳接收及轉傳中繼站以提升系統效能。我們使用馬可夫鏈分析系統效能的理論值，與模擬結果進行比對驗證，最後利用數值模擬結果評估我們提出的中繼站選擇機制的系統效能，並與現行其他方法做比較。

In this thesis, we study the relay selection problem for a buffer-aided and energy harvesting cooperative system. A number of relays harvest energy from the source signal and one relay are selected to forward the source signal using the harvested energy. Since the harvested energy is often weak, the best practice is to accumulate the harvested energy by storing it into the rechargeable battery. With the aid of energy and data storage, both limited in size, an important question is how to determine the action of each relay, namely receiving data or forwarding the source signal. A relay selection scheme, called dual buffer relay selection (DBRS) is proposed considering the data buffer, energy buffer and channel status simultaneously. To evaluate the performance of DBRS, theoretical analysis based on Markov chain model is performed. Simulation results are presented to validate the analysis accuracy and get insights into the system performance subject to numerous key parameters.

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