隨著影音串流以及手機遊戲的普及，人們對於通訊網路的需求越來越高，與此同時，新興的通訊網路技術 5G 也逐漸步入商業化，移動式互聯網路成為人們不可或缺的一部份，5G 網路使用高頻段的 mmWave，因為此頻段的傳播距離短，所以必須大量的部屬基地台，此種部屬方式容易導致過多的基地台與使用者的連接處於不平衡的狀態，造成眾多基地台閒置而引起過度的能源消耗問題，因應國際碳排放公約，有越來越多國家逐漸重視碳排放的議題，且許多的大型企業也加入了環境保護綠色節能的公約 RE100。綠能議題逐漸受到重視，本篇論文考量了異質型網路，將以關掉蜂巢式區域內的部分微小型基地台，來達到提升能源的利用度，通篇採用隨機幾何的模型架構，普松分配的基地台部屬方式，並設定路徑損失係數，基地台功率，以及使用者密度，連結策略等，並採納以單位細胞內使用者個數為依據，對二階層的異質型網路的覆蓋率及連線機率進行分析，我們提出了一種新的睡眠機制及使用者連線策略來提高能源效率，具體而言，我們關閉了基地台，依據基地台範圍內的使用者個數少於特定的數量，並且將此服務區域內的使用者連結至基地台，根據隨機幾何的網絡模型，我們給出了連接概率和覆蓋率的解析表達式。我們還提供數值分析結果和模擬結果。

With the advancement of technology in recent years, the traffic of communication
networks has been growing explosively. In order to solve this problem, a large
number of small base stations are placed on the heterogeneous network, but it also
leads to excessive energy consumption. In this paper, we establish the user scenario in off-peak hours and use sleeping base stations to save power. This paper discusses a two-tier heterogeneous network architecture and adopts a base station shutdown strategy based on the number of users. If the number of users in a small cell is less than the threshold value we set, we shut down the small base station. We also analyze the connection probability of users under various conditions and study the connection quality of users using a stochastic geometric model to derive the energy efficiency. Finally, we validated the results of the mathematical model by simulation.

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