臺灣博碩士論文加值系統

免執照LTE (LTE Unlicensed, LTE-U)和授權輔助接取 (Licensed-Assisted Access, LAA)為卸載LTE訊務至未授權頻段的新興接取模式，如何在未授權頻段與Wi-Fi共存便成為了重要的議題。於本論文中，吾人提出一具有服務品質 (quality of service, QoS) 需求之訊務平衡策略，該策略透過允入控制保證小細胞用戶於授權頻段的服務品質，並考慮小細胞用戶於未授權頻段與Wi-Fi用戶的資源分配，此外，吾人提出一分散式之小細胞功率適應演算法，此演算法目的為降低小細胞功率消耗，同時維持小細胞吞吐量。最後，電腦模擬結果顯示，吾人所提出之訊務平衡策略能有效提升網路表現，功率適應演算法亦能提供較低之功率消耗。

LTE unlicensed (LTE-U) and licensed-assisted access (LAA) are new access schemes which allow the coexistence with Wi-Fi to offload the LTE traffic in the licensed band. Fair and efficient coexistence between LTE and Wi-Fi is thus a key issue to be addressed. In this thesis, a traffic balancing strategy with guaranteed quality of service (QoS) is proposed to maximize system capacity and user satisfaction. The proposed method considers unlicensed band resource partition to achieve fair coexistence with Wi-Fi and performs admission control in the licensed band to guarantee QoS. Moreover, We propose a distributed small cell power adaption algorithm aimed at reducing power consumption for small cells while maintaining cell throughput. Finally, computer simulations shows that the proposed traffic balancing strategy can effectively improves network performance, and the proposed power adaption algorithm can help reduce power consumption.

Chinese Abstract i
English Abstract ii
Table of Contents iv
List of Figures vi
List of Table vii
Acronym Glossary viii
Notations ix
Chapter 1 Introduction 1
Chapter 2 System Model 4
2.1 Network Architecture 5
2.2 QoS Constraints 6
2.3 Traffic Pattern Model 8
2.4 Summary 11
Chapter 3 Traffic Balancing Strategy in Unlicensed Band 12
3.1 Background and Motivation 14
3.2 Problem Formulation 16
3.3 Proposed Traffic Balancing Strategy 18
3.4 Computer Simulations 20
3.5 Summary 28
Chapter 4 Small Cell Power Adaption for Power Saving 29
4.1 Proposed Small Cell Power Adaption Algorithm 30
4.2 Computer Simulations 34
4.3 Summary 36
Chapter 5 Conclusions and Future Works 37
Bibliography 39

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