多接取行動邊緣計算被認為是解決行動應用需求快速增長的有效解決方案，行動用戶能夠透過此技術將延遲敏感的任務卸載到邊緣伺服器進行運算。本論文利用速率拆分多址接取技術來支援多邊緣伺服器的計算卸載，用戶將數據分為每個邊緣伺服器都需要接收的公有訊息和專用於特定邊緣伺服器的私有訊息，透過調整拆分數據同時卸載到多個邊緣伺服器。在本論文中，我們的目標是共同優化公有和私有訊息的傳輸功率和速率分配以及分配給每個邊緣伺服器的任務量來最小化完成用戶計算任務的延遲。由於優化問題是非凸的，我們通過推導一系列最優傳輸功率的封閉表達式來簡化問題，接著，在一特殊條件下將問題轉換為較簡單的形式，最後，我們使用兩階段二分搜索演算法尋找簡化問題的最優解，並以數值結果顯示比較所提出的速率拆分多址接取多邊緣伺服器計算卸載的效能與基於非正交多址接取的多邊緣伺服器方案之性能。

Multi-access mobile edge computing (MEC), which enables mobile users to offload delay-sensitive tasks to edge servers, has been considered as a promising paradigm to address the rapid growth of computation demands from mobile applications. This work exploits Rate-Splitting Multiple Access (RSMA) to support multi-MEC computation offloading, in which the user divides the data into the common message and the private one. By properly adjusting the proportion of the common message to the private one, data offloading to multiple MEC servers can be performed simultaneously. In this work, we aim at minimizing the delay for finishing user's computation task by jointly optimizing the transmit power and rate allocation for common and private messages as well as the amount of tasks allocated to each edge server. Since the formulated optimization problem is non convex, problem transformation is concluded by deriving a series of closed-form expressions for the optimal transmit power. Then, a special case is considered to reduce the problem into a simpler form. Finally, the two-stage bisection search (BSS) algorithm is used to find the optimal solution of the simplified problem. Numerical results are presented to demonstrate the performance of the proposed RSMA-enabled multi-MEC computation offloading in comparison with the non orthogonal multiple access (NOMA)-enabled multi-MEC scheme.

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