臺灣博碩士論文加值系統

隨著第五代行動通訊網路(5th generation mobile networks)在台灣商轉，相較過 去使用的 4G 網路，連網設備的數量與連線品質的需求更是要更高等級的水準。為 了讓具有移動性的使用者有更好且穩定的連線品質，會面臨到的一項議題便是換 手(Handover)，如何改善換手來讓使用者設備都是在良好的連線狀態，便是探討的 方向之一。對於大量 UE 具有相同移動路徑的環境下，容易換手到同一個基地台， 使該基地台負載過高，導致資料下載量減少，為解決此問題，本文提出了以使用者 設備的下載速率來做為換手評估的優先值，此優先值即為換手基地台的選擇依據， 每次換手就會計算一次優先值，因此可以動態調整每次的選擇策略，在大量使用者 設備且具有相同移動模式的環境下，可以平均分散基地台的負載量，進而提升總體 的資料傳輸量。 實驗結果表明，本文方法與負載均衡相關方法相較之下，本文方法可以有較高 的平均資料傳輸率，但也產生較多的換手次數，以提高資料傳輸量而言，本文方法 是有達到此目的。

The 5G market is moving fast in Taiwan. 5G supports massive data traffic with large bandwidth and low latency. When lots of user equipment moves in the same way. A tremendous increase in handover scenarios and handover rates will occur. It leads the high load of the base station. To reduce the loads, this article proposed a scheme to distribute the load of the base station to other base stations. We refer to the user downlink to the priority score to decide the handover strategy. The priority score is adjusted dynamically by the bandwidth of the user downlink. Therefore, the priority score can distribute the loads of the base stations. The average bandwidth of the downlinks will be increased for the balanced loading of base stations. The experiment shows that the proposed scheme outperforms LTE-A3 method and other loading balance method.

摘要 I
ABSTRACT II
誌謝 III
目錄 IV
圖目錄 VI
表目錄 VIII
第一章 緒論 1
1.1研究背景 1
1.2研究動機 5
1.3論文架構 6
第二章 相關研究 7
2.1 換手流程 7
2.2 換手議題 10
第三章 研究方法 15
3.1 方法簡述 15
3.2 換手流程 17
3.3 訊號層級 19
3.4資料表內容與優先值計算 20
第四章 實驗與分析 23
4.1 方法比較 23
4.2 實驗流程 24
4.3 實驗環境 25
4.4 實驗分析 27
4.4.1 改變UE數量 27
4.4.3 改變UE的移動速度 30
第五章 結論與未來工作 34
參考文獻 35

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