在密集布建長期演進技術(Long Term Evolution, LTE)小細胞基站(Small Cell)的情況下，可能會有很多Small Cells涵蓋範圍互相重疊，當一個Small Cell在沒有任何使用者設備(User Equipment, UE)時，如果沒有進入省電模式會造成功率的浪費，因此本論文提出一個針對小細胞基站的省電與喚醒機制(Power-saving and Wake-up Mechanism, PWM )，在PWM中，省電模式是將Small Cell的部分模組(射頻模組和LTE相關程式等)關閉，但是當一個UE進入處於省電模式的Small Cell涵蓋範圍且沒有其他Small Cell可服務此UE時，可能會造成此UE無法連線，因此我們另外替Small Cell設計一個喚醒機制，此喚醒機制會喚醒處於省電模式的Small Cell。
我們使用工業技術研究院(Industrial Technology Research Institute, ITRI)的Small Cell平台實作PWM，我們新增監控每個UE的參考訊號接收功率(Reference Signal Received Power, RSRP)的RSRP Monitor模組，除此之外，我們還新增資料庫管理(Database Manager)模組，此模組會將每個Small Cell與UE的連線狀況記錄在一個資料庫中，最後，我們新增Power-saving模組和Wake-up模組，這兩個模組的功能是發送指令給Small Cell使其進入省電模式與喚醒。在實作完成後，我們會量測UE的訊號強度與Small Cell的功率消耗來驗證本論文所提出的PWM確實具有省電的功能，而且當一個UE進入Small Cell範圍時可以恢復服務功能。

For densely placed LTE (Long Term Evolution) small cells, many of them may overlap in coverage. When a small cell does not serve any user equipment (UE) and no power-saving mode is supported, it will result in the large waste of power. Therefore, this thesis presents a Power-saving and Wake-up Mechanism (PWM) on LTE small cells. In the proposed PWM, power-saving mode is to turn off some modules, such as radio frequency modules and LTE related programs. However, when one UE enters the coverage of a small cell with power saving mode and no other small cells can serve the UE, this UE may lose connection. We also design a wake-up mechanism for small cells. This wake-up mechanism will power on the small cell in the power-saving mode. We use ITRI’s (Industrial Technology Research Institute) LTE-small cell platform to implement the PWM. We add a RSRP (Reference Signal Received Power) monitor to control RSRP for each UE. Additionally, we add a database manager module, which records the connection status of each small cell and each UE in the database. Finally, we add power-saving and wake-up module, the function of these two modules is to send a command, which allows a small cell to enter the power-saving mode and awakened. After the implementation, we measure the signal strength of a UE and the power consumption of a small cell to verify that the proposed PWM can effectively save power and recover to the serving status when a UE enter to its coverage.

致謝 i
摘要 ii
Abstract iii
目錄 iv
圖表目錄 vii
第一章 導論 1
1.1 研究動機 1
1.2 研究方法 1
1.3 章節介紹 2
第二章 LTE 小細胞基站的省電機制 3
2.1 LTE 的標準 3
2.1.1 SON 5
2.1.2 UE 的連接服務、中斷服務與換手 5
2.1.3 觸發與換手事件 11
2.1.4 Measurement Report 12
2.2 ITRI Small Cell 14
2.3 相關研究 15
2.4 本論文機制 16
第三章 小細胞基站的自動省電與喚醒 17
3.1 PWM 的系統功能 17
3.2 RSRP Monitor 模組 19
3.3 DM 模組 20
3.3.1 DM 模組與MME 間的通訊 22
3.3.2 Small Cell 的開啟 23
3.3.3 UE 連線服務 24
3.3.4 UE 主動中斷服務 25
3.3.5 UE 離開服務範圍 26
3.3.6 UE 換手 27
3.4 SCP 模組 28
3.5 SCW 模組 29
第四章 ITRI 平台實作與結果分析 31
4.1 實驗環境與設備規格 31
4.2 在ITRI 平台上的實作 32
4.2.1 RSRP Monitor 模組的實作 33
4.2.2 DM 模組 38
4.2.3 SCP 模組 49
4.2.4 SCW 模組 51
4.3 實驗結果與分析 55
4.3.1 實驗內容與參數設定 55
4.3.2 Small Cell 省電模式的分析 57
4.3.3 Small Cell 喚醒機制的分析 61
4.3.4 PWM 的省電結果分析 62
第五章 結論與未來工作 63
5.1 結論 63
5.2 遭遇的問題 64
5.3 未來工作 65
Reference 66
Acronyms 69
Index 71

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