在可移動的環境中，如何節省移動裝置的電力來增加它的持續使用時間一直是個重要的議題。 在這篇文章中，我們針對 IEEE 802.16e 中 Type II 的 Power Saving Classes 提出一個節省電力消耗的方法，稱為Maximum Unavailability Interval (MUI)。 當移動裝置處於Unavailability Interval中時，移動裝置可以將它的無線電收發器 (Transceiver) 關閉來節省電力並延長使用時間。
我們把中國餘式定理 (Chinese Remainder Theorem) 應用在我們提出的MUI中來計算出最大的Unavailability Interval，藉此可節省最多的電力。 IEEE 802.16e的標準中，Type II 的 Power Saving Classes 定義了三個參數： (1) sleep window， (2) listening window， (3) start frame number。 第一和第二的參數會根據 Power Saving Class 中包含連線的服務品質 (QoS，Quality of Service) 的要求來設定。 我們提出的MUI中，只會動態的調整第三個參數，也就是Power Saving Class啟動的時間，所以不會影響到服務品質的要求。 由於MUI是用於調節器 (Scheduler)中，而調節器不在標準的定義範圍，所以沒有變動到 IEEE 802.16e 標準中定義的任何程序，是完全相容於IEEE 802.16e。
我們更進一步提出 Table-based Algorithm 來降低直接使用中國餘式定理的計算複雜度。 最後，我們用分析和模擬來驗證三種方法的效能，此三種方法包括：暴力法，直接使用中國餘式定理的方法，和使用Table-base Algorithm的方法。 分析和模擬都顯示出Table-base Algorithm在效能上優於另外兩種方法。

In mobile environment, how to extend the life time of mobile devices is an important issue. This thesis presents an energy conservation scheme, Maximum Unavailability Interval (MUI), to improve the energy efficiency for Power Saving Class of Type II in IEEE 802.16e. By applying the Chinese Remainder Theorem, the proposed MUI is guaranteed to find the maximum Unavailability Interval, during which the transceiver of a mobile station can be powered down. In Type II, there are three parameters: (1) sleep window, (2) listening window, and (3) start frame number. The proposed MUI only dynamically adjusts one parameter, the start frame number. The other two parameters are set according to Quality of Service (QoS) requirements of the connections. Our proposed scheme will not change them. In addition,
our proposed scheme is fully compatible with 802.16e standard. We also propose a new table-based algorithm to reduce the computational complexity when solving the Chinese
Remainder Theorem problem. Simulation and analysis have been conducted to evaluate and compare the performance of the proposed MUI using Chinese Remainder Algorithm and Table-based Algorithm with a brute force algorithm. Both simulation and analysis show that the proposed MUI with table-based algorithm performs better than the other two schemes.

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