計劃中文名稱: 在LTE行動通訊網路上動態調整Handover臨界值的卸除負載機制

中文計畫摘要：
本計畫在LTE Small Cell中提出一個動態調整Handover臨界值(Dynamic Adjustment in Handover Thresholds, DAHT)的換手機制來卸除某些負載過重的eNB，DAHT換手機制除了考慮User Equipment (UE)是處於靜止或移動狀態，也能夠利用Evolved Node B (eNB)的負載來計算出換手因素(Handover Factor, HF)，Source eNB藉由HF來減小或增大Source eNB與Target eNB的Reference Signal Receiving Power (RSRP)之間的差值(Offset)，因此Source eNB能夠將UE提前或延遲換手到Target eNB。 為了完成所提出的DAHT換手機制，本計畫總共需要兩年，第一年，我們將在eNB上設計負載量測模組來定期量測與回報eNB的負載，並在eNB上設計UE換手模組來進行UE的提前或延遲換手，另外我們也在Evolved Packet Core (EPC)的Self-Organizing Network (SON)上設計負載狀態分類模組來將每台eNB的負載做高中低的分類，並在SON上設計負載卸除模組來計算eNB所需要卸除負載的大小。最後，為了驗證我們所提出的DAHT換手機制的優越性，在本計畫的第二年，我們將使用工研院(Industrial Technology Research Institute, ITRI)提供的Small Cell平台與EPC軟體來實作完成上述四個模組，在實作完成後，我們將量測eNB的負載狀態與UE的居留時間以證明本計畫所提出的DAHT換手機制可以完成提前與延遲換手以達到卸除負載的目的。

關鍵字 ：LTE、Small Cell、負載卸除、EPC、SON、換手。

計劃英文名稱: Dynamic Adjustment in Handover Thresholds for Off-Loading in LTE Mobile Communication Networks

英文計畫摘要：
In this project, we propose a Dynamic Adjustment in Handover Thresholds (DAHT) for off-loading in LTE small cells. The proposed DAHT can distinguish whether an User Equipment (UE) is in static or mobile status. Additionally, DAHT can off-load Evolved Node B (eNB) by calculating a Handover Factor (HF). Based on the HF, source eNB can decrease or increase the offset of Reference Signal Receiving Power (RSRP) between source eNB and target eNB. Therefore, source eNB can advance or delay handover of UE to target eNB. To construct the proposed DAHT scheme, this project requires two consecutive calendar years. In the first year, we will design the load measurement module on eNB to periodically measure and report the load of eNB, and design UE handover module on eNB to advance or delay UE’s handover. Moreover, we design load status module on Self-Organizing Network (SON) of Evolved Packet Core (EPC) to classify the load status of an eNB (i.e., heavy, medium, and low). Finally, we design offloading module on SON to calculate the off-loading amount. In the second year, to validate the superiority of the proposed DAHT, we implement the aforementioned modules on ITRI’s (Industrial Technology Research Institute) small cell platform. After the implementations, we will measure the load status of eNB and the residence time of UE to prove that the proposed DAHT can achieve advance or delay handover and the goal of off-loading.

關鍵字 ：LTE, small cell, off-loading, EPC, SON, handover.