透過獵能技術可以延長無線裝置及網路的壽命，而作為其一項應用，無線獵能中繼站使用由無線電訊號採集到的能量協助訊息的轉傳，並可取代傳統固定電源供電的中繼站以建立一個高自立性的合作式網路。由於獵能的過程中會受到無線通道衰減及無線電能量轉換效率的限制，如何有效地使用採集的能量將成為一個重要的議題，同時，中繼站如何對於訊息轉傳及獵能兩項任務進行排程與資源分配亦與整體系統效能密切相關。本篇論文針對無線獵能之合作式通訊系統，基於分時多工討論不同的傳送排程，包括時間重用模式排程及全雙工模式排程，且同時考量獵能及訊息轉傳的通道狀況，做出合適的中繼站選擇。針對所提出的選擇機制，我們提供中斷機率及系統產量的理論分析，探討不同距離衰減、中繼站數量及傳送速率造成的影響，並透過模擬結果驗證理論分析正確性。

Energy harvesting (EH) is an attractive solution to prolong the lifetime of wireless devices. As the replacement of traditional battery-powered relay nodes, EH relays extract energy from the signal of the source node and use the harvested energy to perform information relaying, enabling a self-sustainable cooperative network. To use the harvested energy efficiently which is limited due to the energy loss by wireless channel impairment and RF-DC conversion, it is important to properly schedule the two tasks for relays, namely information and EH, within a transmission block. In this thesis, we investigate block scheduling and relay selection problems in a cooperative networks with EH relays. In terms of block scheduling, we consider two variants of time division multiplexing, including partial time reuse and full-duplex scheduling. In terms of relay selection, we propose a relay selection scheme where selected max-max relay selection (S-MMRS) considers both the source-relay channel for EH and the relay-destination channel for information relaying in selecting the cooperating relay. To evaluate the performance of the proposed S-MMRS, we theoretically analyze the outage probability and the throughput and the simulation results are presented to verify the analysis accuracy and demonstrate the impact of system parameters to the proposed relay selection scheme.

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