機器類型通訊為次世代蜂巢式網路所提供的一種新型態服務。若大量機器類型通訊裝置在同時間欲與基地台建立連線會造成無線接取網路超載問題，而這個問題可能會嚴重影響原先人與人的通訊服務品質。本篇論文針對3GPP中所討論的時槽式存取超載控制機制提出一個分析模型，以分析同時間下機器和人與人兩種訊務類型的效能表現 ，其中包含資源碰撞機率，裝置成功存取機率，資源使用效率，成功存取傳送次數累積分佈函數，成功存取延遲時間累積分佈函數。此外本篇論文還有探討在考慮人與人的通訊服務品質下，如何決定存取周期使整個系統資源達到最佳使用效率。最後根據模擬結果可驗證本篇論文所提出之分析模型可準確分析出同時間下機器和人與人兩種訊務類型的效能表現。

Mass machine-type communications (MTC) devices simultaneously access the random access channel (RACH) may result in radio access networks (RANs) overload and degrade the performance of the human-to-human communications (H2H) services. Slotted access scheme is one of the mechanisms proposed in 3GPP for the RAN overload protection. This thesis aim to propose an analytical model which considered both MTC and H2H traffic for slotted access scheme and derive the performance metrics that include the collision probability, access success probability, statistics of number of preamble transmission, statistics of access delay and utilization. Besides, the optimal access cycle for different MTC traffic is derived to maximize the utilization of the random access channel on the guaranteeing of quality of service (QoS) for H2H traffic. Numerical results demonstrate the proposed model can accuracy estimate the performance metrics of slotted access scheme.

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[16]3GPP R1-060584, “E-UTRA Random Access,” Ericsson, RAN1#44, Denver, USA, Feb 2006.
[17]3GPP TS 36.300, “Evolved universal terrestrial radio access (E-UTRA) and evolved universal terrestrial radio access network (E-UTRAN) overall description,” v. 11.1.0, March 2012.
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