5G超密集網絡的能量效率研究綜述

摘要: 首先從綠色通信入手, 對網絡能量效率的國內外研究現狀進行了分析. 在此基礎上, 對超密集網絡的關鍵性能指標, 即能量效率的各種定義進行了梳理, 為建模奠定了基礎. 其次, 討論了網絡能量效率建模和優化過程中經常使用的4種理論模型: 隨機幾何、博弈論、最優化理論和分數階規劃. 并綜述了能效提升的技術, 包括高能效部署與規劃、高能效基站休眠、高能效用戶關聯、高能效資源管理、高能效傳輸方式. 最后, 指出未來的可能的技術挑戰: 網絡能效理論與超密集網絡體系架構、超密集小基站高能效覆蓋機理、超密集網絡的柔性資源匹配機理、移動用戶群體行為建模與高能效服務方法. 通過研究超密集網絡高能效覆蓋機理和柔性資源匹配機理, 為未來無線通信網絡建模和分析提供設計依據與技術支撐.
- 能量效率 /
- 5G /
- 超密集網絡 /
- 用戶關聯 /
- 無線資源分配
Abstract: Fifth generation (5G) cellular networks are expected to achieve high data rates, reduced latency, increased spectrum efficiency, and energy efficiency. Ultra-dense networks (UDNs), a key enabling technology in 5G cellular networks, are envisioned to support the deluge of data traffic located in hotspots and at cell edges, and to enhance quality of experience of mobile users. UDNs can significantly improve the spectrum efficiency and energy efficiency to achieve sustainability of 5G. However, the deployment of a large number of small cells poses new challenges for energy efficiency. Recently, the energy efficiency of UDNs has become a prime concern in the operation and architecture design owing to environmental and economic effects. Therefore, it is significant to study the energy efficiency of UDNs. This survey provided an overview of energy-efficient wireless communications, and reviewed seminal and recent contribution to the state-of-the-art. Therefore, the definitions of energy efficiency, a key performance indicator of the UDNs, are analyzed, which is a foundation for modeling. Four theoretical models, which were often used in the modeling and optimization of energy efficiency, were discussed. These models include stochastic geometry, game theory, optimization theory, and fractional programming theory. Energy-efficient techniques of UDNs were also reviewed. These technologies include energy-efficient deployment and planning, a base station sleeping mode, user association, radio resource management, and transmission. Finally, the most relevant research challenges were addressed, including the theory of energy efficiency of UDNs, architecture of UDNs, the high energy efficiency coverage mechanism of ultra-dense small base stations, the flexible radio resource matching mechanism of UDNs, group behavior modeling of mobile users, and high energy efficiency service methods. This review of the energy-efficient coverage mechanism and flexible radio resource matching mechanism in UDNs provides design guidelines and potential solutions for analytical modeling of future wireless networks.
- energy efficiency /
- 5G /
- ultra-dense networks /
- user association /
- radio resource allocation

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圖 1 快速增長的業務量與能耗之間的矛盾

Figure 1. Contradiction between the rapid growth in traffic and energy consumption

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圖 2 基站功耗構成示意圖

Figure 2. Schematic of energy consumption of base stations

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圖 3 基于最優化理論的模型求解與分析過程

Figure 3. Flow chart of the model solution and analysis based on optimization theory

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圖 4 密集網絡的多層重疊覆蓋部署模型

Figure 4. Deployment model of ultra-dense networks

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