中繼點的選擇是在多跳中繼網絡的一個關鍵問題。在這篇論文中，對於兩跳中繼網絡的一個新的跨層中繼選擇方案，提出了利用一種新的效用函數為中繼選擇標準。同時考慮信道狀態信息（CSI）的物理層和隊列狀態信息（QSI）在數據鏈路層所提出的選擇方案，旨在保證不同服務的不同QoS要求。隊列狀態信息被用來評估中繼選擇發送的不同的服務速率的變化造成的影響。此外，不同級別的優先級分配給每個服務來表示每個服務的不同QoS的嚴格性。我們的模擬結果表明，該算法優於其他中繼選擇方案在滿足巨觀和微觀的QoS滿意度方面。

Relay selection is a key issue in multi-hop relay networks. In this thesis, a new cross-layer relay selection scheme for two-hop relay networks is proposed, which utilizes a novel utility function as the relay selection criterion. The proposed selection scheme which considers both channel state information (CSI) at physical layer and queue state information (QSI) at data link layer, aims to guarantee the diverse QoS requirements for different services. The queue state information is used to evaluate the impact of relay selection on change of transmitting rate of different services. Moreover, different levels of priority is assigned to each service to represent the different QoS stringency of each service. Our simulation results show that the proposed algorithm outperforms other relay selection schemes in terms of satisfying frame-level and slot-level QoS satisfaction.

Abstract i
Table of contents ii
List of figures iii
Chapter 1 Introduction 1
1.1 Motivation 1
1.2 Related work 2
Chapter 2 System model and a simple greedy scheme 4
2.1 System model 4
2.2 A simple greedy scheme 6
Chapter 3 Relay selection scheme 10
Chapter 4 Simulation 14
4.1 Compared algorithm 14
4.2 Simulation settings 15
4.3 Simulation results 16
4.3.1 Dynamic traffic injection rate 16
4.3.2 Fixed traffic injection rate 23
Conclusion 23
Reference 27

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