在本論文中，我們針對非完美通道資訊情境探討適用於下行多載波非正交多重接取(NOMA) 系統的資源分配方法，包含子載波分配、功率分配及使用者配對。為了簡化此一複雜的資源分配問題，我們分別處理上述資源分配項目，並發展一個次佳的解決方案以最小化系統中斷機率的平均上界。我們所提出之資源分配程序乃以一個子載波接著一個子載波的方式進行，直到所有子載波皆已分配給使用者為止；另外，此一資源分配方法還考慮了使用者間子載波分配的公平性，以便使用者可以均勻分享通道資源。對於一個包含N個子載波和K個使用者的下行NOMA系統，所提出的方案具有大約O(0.5KN2+N2) 的低時間複雜度；電腦模擬結果也顯示，所提出的資源分配方法比使用相同子載波分配機制和相同功率分配方式的相關資源分配作法，具有較佳的系統效能。

In this thesis, we investigate resource allocation including subcarrier assignment, power allocation, and user pairing for a downlink multicarrier non-orthogonal multiple access (NOMA) system under imperfect channel state information. To simplify the resource allocation problem, we deal with subcarrier assignment, power allocation, and user pairing separately to develop a suboptimal solution based on minimizing the average upper bound of an outage probability. The resource allocation procedure is performed on a subcarrier-by-subcarrier basis until all subcarriers have been assigned to users. In addition, it considers fairness of subcarrier assignment among all users such that all channel resources can be shared by all users in a uniform way. For a downlink NOMA system with N subcarriers and K users, the proposed scheme involves low time complexity of about O(0.5KN2+N2). Computer simulation results also demonstrate that it achieves better system performance than related schemes using the same subcarrier assignment mechanism and the same power allocation method.

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