在一方面，由於計算複雜的電路快速消電池能量，所以資料的無線傳輸速率受限於電池容量。在另一方面，行動裝置的移動性所提供的自由度相當受到人們歡迎。因此，如何延長行動裝置的電池壽命就變成最重要的議題之一。因此，3GPP LTE-advance無線網路使運用一稱為DRX的節能運作去延長電池的壽命。然而，使用DRX卻會增加封包的延遲。因此如何在省電以及封包延遲間取得平衡值得我們探討。此外，不同的服務可能會有不同的服務品質需求。舉例來說，即時性的服務對於封包延遲較為敏感；然而非即時性的服務對於封包遺失較為敏感。因此，如何將DRX與服務差異性做結合也是非常重要的議題。在此篇研究中，我們專注在使用DRX的LTE-advanced網路的封包下載傳輸。我們假設系統有兩種類別的行動裝置，且每種類別都有多於一行動裝置。而這些行動裝置都進接到同一個UTRAN。我們感興趣的效能指標有功率節能因子、喚醒延遲以及平均功率消耗百分比。第一，為提高整體成功送達率，我們提出一種多工型DRX方法以使得，在一次最多只能傳送一個封包的限制下，多於一個行動裝置可以進接到UTRAN。第二，為了減少計算複雜度，我們以半馬可夫程序為基礎提出了兩種近似方法去計算我們感興趣的效能指標。第三，我們考慮每一行動裝置都具有相同優先權的情境。我們探討各種系統參數對於不同效能指標的影響。第四，我們考慮兩種類別的行動裝置擁有不同優先權的情境。我們提出四種方法來達成服務差異化。我們探討各種系統參數如何影響具有不同優先權的行動裝置的效能指標。最後，我們使用電腦模擬來驗證解析結果，其中電腦模擬與解析程式是分別以C與Matlab來撰寫。

On one hand, the data rate for wireless transmission is limited by battery capacity because the computationally complex circuitry drains the battery energy quickly. On the other hand, people enjoy the freedom provided by the mobility of user equipment (UE). Therefore, how to extend the battery lifetime of UEs is one of the most significant issues. Accordingly, Third-Generation Partnership Project (3GPP) Long-Term Evolution Advanced (LTE-Advanced) wireless networks employ the power-saving operation called Discontinuous Reception Operation (DRX) to improve UE battery lifetime. On the other hand, DRX will lead to the increase of latency. How to strike a balance between power saving and latency is worth studying. Furthermore, different service may have different QoS requirements. As an example, real-time services are delay-sensitive, whereas non-real-time services are loss-sensitive. Therefore, how to combine DRX with service differentiation is also a worthy topic. In this work, we focus on the downlink packet transmission of the LTE-advanced network with DRX. It is assumed that there are two classes: class-A and class-B, and each class has more than one UE. And these UEs access the common UTRAN. The performance measures of interest are power saving factor, wake up delay, and mean percentage power consumption. First, to increase the aggregate throughput, we propose a multiplexed DRX scheme to allow more than one UE accessing the common UTRAN under the constraint that at most one packet can be transmitted at a time. Second, to reduce the computational complexity, we propose two approximation methods based on semi-Markov processes to calculate the performance measures of interest. Third, we consider the scenarios where each UE has the same priority. We study the effect of various system parameters on different performance measures. Fourth, we consider the scenarios where two classes of UEs have different priorities. We propose four different schemes to provide service differentiation. We study the effect of various system parameters on different performance measures of UEs with different priorities. Lastly, the analytical results has been validated against simulation results, and the computer simulation and analytical programs are written in C and Matlab, respectively.

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