隨著行動用戶對於多媒體應用服務使用量的增加，長期演進技術(LTE)可提升資料傳輸的品質。由於使用者會在基地台之間移動，進行系統內的基地台交遞(LTE handover)。使用者在作基地台交遞時，與系統會有一段分離的時間，此時來源基地台(Source eNodeB)會把正在傳送給使用者的資料轉送到目的基地台(Target eNodeB)。由於基地台之緩衝存儲器容量有限，資料轉送的延遲或資料遺失將會影響到系統效能，使得使用者的服務品質下降。為了增加系統效能，本論文提出三種演算法。分別為阻擋演算法(Blocking)、丟棄時間最久的議程演算法(DOS)及丟棄資料最多的議程演算法(DHS)。當在目地基地台的緩衝存儲器(buffer)開始溢滿時，此三種方法主要是透過丟棄在緩衝存儲器中的資料，進而提升系統效能。因此我們提出一個模擬模型，利用此三種演算法去測量不同容量的緩衝存儲器對系統的影響。我們從實驗結果中發現，丟棄資料最多的議程演算法的效能表現優於其他兩種演算法。

With the increasing of requirements of multimedia services, Long Term Evolution (LTE) technology can improve the quality of high speed data transferring. Due to the movement of UE among base stations, LTE system performs handover. A LTE handover occurs a detach time when user moves form source eNdoeB to target eNodeB. The source eNodeB forwards user data to target eNodeB instead of UE during this interrupt time. This procedure will degrade the system performance according to the delay or lost transmitting data. In order to promote system performance and provide a good service to users during LTE handover, this paper proposes three buffer management algorithms as Blocking, Dropping the Oldest Session and Dropping the Heaviest Session without any modification of handover procedure. When the buffer of target eNodeB is overflowing, the packets in the buffer are discarded through our algorithms. Simulation model is developed to measure the effects on the buffer size. The simulation results show that the DHS has the best performance among our methods.

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