在本篇論文中，我們致力於在密集的小細胞網路中設計低複雜度的基
地台睡眠方案來提升能量效益。我們通過兩個部份來解決問題，首先藉由能量效益的標準來建立初始的使用者連線，對此運用Gale-Shapley演算法來解決基地台與用戶裝置之間的雙方匹配問題。接著在每次迭代中，若具有較低能量效益的基地台所服務的使用者能在提供所需的服務品質下與其他基地台重新連線，則我們可以將其轉換為睡眠狀態。為了改善使用者對於其他基地台重新連線的成功率，所有能夠滿足使用者服務品質要求的基地台將成為可以被重新建立連線的目標。與先前的方案相比，我們所提出的方法能夠顯著的提升能量效益並且能夠增加關閉基地台的數量。

In this thesis, we aim to enhance the energy-efficiency (EE) for hyper-dense small-cell networks (SCNs) by designing a low-complexity sleeping strategy for base-stations (BSs). We approach this problem by two steps. Firstly, initial user associations are developed based on the criterion of maximizing EE. To this end, the Gale-Shapley algorithm is applied to solve the bipartite matching between the user equipments (UEs) and BSs. Second, the BSs with lower EE are iteratively considered to switch into sleeping mode on the condition that all served UEs can be reassociated with provisioning of quality-of-service (QoS). To improve the success rate of reassociation, all the BSs that can reach the predefined QoS are feasible target BSs. Compared with conventional schemes, remarkable enhancement of EE can be achieved and more BSs can be switched off by using the proposed method.

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