隨著科技的快速進步，衛星通訊由於具有覆蓋範圍大、可擴展性大和通訊容
量大等特性，因此，對於我們的日常生活更顯重要。但是，受限於傳統硬體的設
計和規劃，使得現有的通訊衛星難以做硬體的升級和系統的維護。因此，軟體定
義衛星網路 ( 成為衛星通訊網路未來發展的趨勢。衛星通訊網路的另一個關
鍵議題是在能源的消耗。這是因為難以更換衛星中耗盡的電池。所以，應用於衛
星的可再生能源在我們的研究中被探討。在本研究中，我們提出運用可再生能源
的 SDSN 的新模型，並著重於該模型的效能評估。在研究中，我們考量了四個情
境：沒有優先權的單 一節點、沒有優先權且運用無限重傳的三個節點、沒有優先
權且運用有限重傳的三個節點，和有優先權的單一節點。我們首先推導出四個情
境的解析模型，並使用疊代演算法求出個別模型的穩態機率分佈和感興趣的效能
指標。接著我們研究了各種系統參數對效能指標的影響。系統參數包括新封包的
平均抵達速率、高優先權封包的平均抵達速率、低優先權封包的平均抵達速率、
能量的平均抵達速率和重傳機率。我們感興趣的效能指標則包含系統的平均封包
數、佇列的平均封包數、在系統中的平均等待時間、在佇列中的平均等待時間、
阻塞機率和系統的成功送達率。第三，我們將 有限重傳的效能指標與無限重傳的
效能指標進行比較。第四，我們將高優先權封包的效能指標與低優先權封包的效
能指標能進行比較。 最後但非最不重要，我們利用 C 語言撰寫相關模型的電腦模擬
程式。在大部分情形下解析結果與模擬結果是很接近的。

The satellite communication becomes more and more important in our daily life with the rapid advance of technology. The satellite communication has the properties of large coverage, large scalability, and large communication capacity. However, the existing satellite communication is hard to upgrade and maintain due to the traditional hardware-based design. The software defined satellite network (SDSN) is expected to be the future trend in satellite communication. Another critical issue in designing satellite communications is energy consumption. This is because it is hard to replace the depleted power source in the space. Therefore, the renewable energy has been applied to satellites to extend the lifetime of satellite batteries. In this research, the new models based on SDSN with renewable energy are proposed, and we focus on the performance evaluation of the proposed SDSN models. In this work, we study four scenarios: one node without priority, three nodes without priority and with infinite retransmissions, three nodes without priority and with finite retransmissions, and one node without priority. First, we derived the analytical models for the scenarios considered. An iterative algorithm is adopted to find the steady state probability distribution and the performance measures of interest. Second, the impact of various system parameters on the performance measures is studied. The system parameters include mean new packet arrival rate, mean high-priority packet arrival rate, mean low-priority packet arrival rate, mean service rate, packet queue capacity, energy queue capacity, routing probability. The performance measures of interest are average number in system, average number in queue, average waiting time in system, average waiting time in queue, blocking probability, throughput. Third, the performance with finite retransmissions is compared with that with infinite retransmissions. Fourth, the performance of high-priority packets is compared with that of low-priority packets. Last but not least, the computer simulation is written to verify the accuracy of the analytical results.

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