在長期演進技術升級版 (Long Term Evolution Advanced; LTE-A) 異質網路架構下，為了解決室內環境中位於死角位置訊號品質不佳和人口密集處頻譜資源不敷使用的問題，3GPP提出利用發射功率較小、成本較低廉的家用基地台 (home evolved node B; HeNB) 來彌補訊號品質不佳和頻譜資源不敷使用的問題。但是，未經事先協調與規畫的 HeNB 大規模佈建卻帶來了細胞間相互干擾及功率耗損的隱憂，於是如何減少細胞間干擾及功率耗損是一個值得探討的議題。此外，都會地區室內環境的用戶數量常會隨著時段而改變，如何在不同時段根據用戶數量有效地管理 HeNB 的開機數量，也是另一個值得探討的議題。
本論文以大型商業建築物的室內環境為研究情境，在大量 HeNB 佈建的環境下有大量的物聯網裝置 (Internet of Things; IoT) 協助用戶定位，故用戶位置均為已知。提出一個以用戶位置為基礎的家用基地台功率控制與動態管理機制，此機制首先以用戶與基地台之間的距離做為選擇服務台的依據。其次以降低細胞間干擾為目的調整位於服務範圍重疊區域用戶的服務台。接著在不影響最遠用戶訊號品質的原則下調降基地站發射功率以更進一步減輕干擾。最後以系統整體容量為依據決定是否將服務用戶數較少的基地台關閉，並將其用戶移至其他服務台。目的是為了提升用戶通道品質、系統容量，以及降低功率耗損。
模擬結果顯示，本論文提出的方法在用戶數量較少時，能有效改善用戶的訊號品質進而提升系統容量，且能有效降低家用基地台平均傳輸功率。但隨著用戶數量的增加，用戶訊號品質的改善效果則不明顯，但仍能有效降低基地台平均傳輸功率，減少系統的功率耗損。

3GPP proposes to use the lower-power and lower-cost base station called home evolved node B (HeNB) in order to solve the problems of poor signal in indoor coverage hole and inadequate spectrum resources in hotspot in Long Term Evolution Advanced (LTE-A) heterogeneous network (HetNet). However, large-scale deployment of HeNBs without planning brings the problems of inter-cell interference and power consumption. Thus, how to reduce the inter-cell interference and power consumption are the important issues.
The number of users change over time in indoor environment of urban areas. How to effectively manage the number of active HeNBs according to the number of users at different time is also an important issue.
In this paper, we consider the indoor environment of large commercial buildings with large-scale deployment of HeNBs. There are also many IoT (Internet of Things) devices to support location services. Thus, the location of users are known. We propose the dynamic management and power control scheme based on user location for HeNB. First, users select the serving base station based on the distance between the user and adjacent HeNBs. Second, we adjust the serving base station of users located in the overlapping area in order to reduce the inter-cell interference. Third, in order to mitigate the interference, we adjust the transmission power of HeNBs only if it doesn’t decrease the signal quality of the farthest user of the HeNB. Last, we try to turn the HeNB which has less users into sleep mode based on the capacity of HeNBs and change the serving base station of users served by the HeNB in sleep mode. The purpose of last step is to increase the channel quality, system capacity and reduce the power consumption.

The simulation results show that the proposal in this paper can improve the signal quality and increase the system capacity in the less users environment. The average transmission power of HeNBs also can be decreased. The proposal can’t improve the signal quality effectively when the the number of users increase, but it still can decrease the average transmission power of HeNBs also can be decreased.

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