隨著行動裝置數量的上升，網路資料的流量不斷增加，大型基地台的負載變得越來越重，為了處理這種情況，小型基地台的概念被提出，而小型基地台是低功率的無線接入節點，這是有效地使用無線頻譜資源的好方法，不過還有許多問題需要被解決，其中之一是小型基地台選擇方案，因此，許多作者依據不同的觀點提出相關選擇方案。本論文中我們用頻譜效率來分析小型基地台選擇方案，同時也考慮了靜態和動態情況，此外，還提出機率的分析來計算一些相關參數，像是當前情況有多少比例的使用者是連不到小型基地台而只能連到大型基地台，利用這個資訊我們可以推算出使用者能夠選擇的小型基地台數量分布，而此分布可以判斷出使用者是否需要做小型基地台的選擇，並且還可以推算出使用者與最近基地台的距離，而距離與訊號強度有關，最後我們用來分析小型基地台選擇方案的結果。

With the rising of mobile users, data traffic is largely increasing. The load of macro cell becomes more and more heavy. To handle this situation, concept of mall cell is proposed. The small cell is characterized by small size and low transmit power. It is a good way to efficiently use radio spectrum resources. But there are still many problems to be solved. One of them is cell selection scheme. However, many authors purposed different schemes with a variety of perspectives. In this thesis, we analyze several schemes with spectrum efficiency in static and mobile situation. Further we propose the analysis with probability method to calculate some related parameters. For example, we can calculate the proportion of users that cannot connect to the small cell. With this information, we can calculate probability distribution function of the number of small cells which are connected by users. We can determine whether or not the users need to do cell selection. And we can calculate the distance between the user and the nearest small cell. Finally, we use it to analyze the result of cell selection scheme.

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