隨著智慧手機與物聯網設備之快速發展，全球行動網路需求隨之增長，根據NGMN對未來行動網路預測，未來五年行動網路數據流量將會成長二十倍。為因應大幅成長的網路需求，第三代合作夥伴計劃(3rd Generation Partnership Project, 3GPP)提出透過大量佈建小型基地台(Small Cell)來提升行動網路容量，但在大量佈建的同時亦增加網路管理之難度，然解決方案自組織網路(Self-Organizing Networks, SON)也在當時一併被提出。
傳統網路在基地台佈建之前需要相當長的時間進行評估，考量基地台佈建的位置、天線角度與功率等設定，設置時需透過網管系統以手動方式修改及調整，但此種方式效率低且成本高，無法適用於4G+、5G密集佈建之網路環境。為解決上述問題，自組織網路透過自動化機制自動調整基地台參數，簡化安裝步驟，降低網路佈建與管理成本，進而提高網路品質。
自組織網路分為自配置(Self-configuration)、自優化(Self-optimization)與自修復(Self-healing)三大功能，本研究著重於自優化中的移動穩定性優化(Mobility Robustness Optimization, MRO)，提出一管理機制透過基地台位置及功率與使用者之位置及行進方向來預測無線連接中斷(Radio Link Failure, RLF)的發生，進而自動調整基地台參數，降低無線連接中斷機率，提高行動網路之移動穩定性。本研究所提出之方法比起其他方法可降低RLF發生1.08%，提升系統移動穩定性。

Global mobile communications have flourished as the 4G+/5G Long Term Evolution (LTE) network technology and applications have become much more diversified. As the difficulties associated with configuration and management mechanisms have increased dramatically, the Self-Organizing Network (SON) has been defined in the Next Generation Mobile Network (NGMN) and relevant research has been conducted in order to improve the operation and the efficiency of the future network.

3GPP has proposed that macro cell will be extracted, and small base stations (Small Cell) will be densely deployed in the future 5G network. Hence, mobility will certainly become a critical issue in the future wireless network. In order to solve such issues, SON mechanisms are proposed to install cells and adjust cell parameters automatically.

This study proposes a Mobility Robustness Optimization (MRO) mechanism to deal with Radio Link Failures (RLF) during the handover process. RLF can be classified into: too late handover, too early handover and handover to wrong cell. This study focuses on these handover failure conditions, considers the parameter defined in 3GPP - A3 Offset, and derives several calculation formulas for handover between cells. The proposed MBRP mechanism is compared with the HO-region and it is able to reduce 1.08% of the RLF percentage. This study reduces the RLF problems and optimizes the handover process in the network, further improving the handover quality of the overall network.

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