在3GPP LTE-Advanced網路中，機器類型通訊是一種新型的通訊。近年來，由於物聯網應用越來越廣泛，機器類型通訊設備的數量將遠大於傳統人類通訊設備的數量，而當大量機器類型通訊設備試著在短時間之內連接網路時，就會造成信號網路過載問題發生在LTE-Advanced網路中。因此在本篇論文中，我們提出一個以預測為基礎，搭配存取限制的方法來解決在LTE-Advanced網路上的信號網路過載問題。在我們的方法中，核心網路中的移動管理實體會記錄週期性連接到網路的機器類型通訊設備的預定傳輸時間，接著移動管理實體會預測所有的信號流量，這是為了當網路已經沒有多餘的資源可以服務大家時，可以避免從機器類型通訊設備來的連接。有了信號流量預測的幫助下，所有會聚集在核心網路的信號流量會被分散，而導致了機器類型通訊裝置成功連接網路的機率增加。除此之外，利用我們所提出的動態保留存取限制方法，可以減少機器類型通訊裝置的存取延遲。此外，我們所提出的方法還提供優先權給機器類型通訊裝置，且幫他們減輕了可能會發生的飢餓問題。模擬結果顯示，將我們提出的方法和3GPP所提出的延伸存取限制方法相比，我們的方法減少了機器類型通訊裝置的存取延遲，同時也增加了他們成功連接到網路的機率。

Machine Type Communications (MTC) is a new type of communication in 3GPP LTE-A networks. The number of MTC devices will be significantly larger than human to human devices in the coming decade due to the proliferation of Internet of Things applications. It may cause the signalling network overload problem in an LTE-A network when a large number of MTC devices try to access network within a short period of time. In this paper, we propose a prediction-based scheme with access barring to solve this problem in LTE-A networks. In the proposed scheme, the Mobility Management Entity (MME) of the core network records the scheduled transmission time of the MTC devices which connect to network periodically. MME then predicts the total signalling traffic load in order to prevent unnecessary accesses from MTC devices while the network has no resources for serving them. With the help of traffic prediction, total signaling traffic of the core network can be dispersed resulting in increase of access success probability of MTC devices. Moreover, access delay of MTC devices can be decreased by using our dynamic reservation with access barring scheme. Furthermore, our proposed scheme provides priority for MTC devices and alleviates the starvation problem of them. Simulation results show that the proposed scheme significantly decreases the access delay and improves the access success probability of MTC devices in comparison with the extended access barring scheme adopted by 3GPP.

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