近年來無線網路研究中，隨著行動裝置的普及以及更多裝置的連網服務，裝置上網的需求逐漸供不應求，傳輸資料量大幅增加，以致於我們必須不斷更新技術或是加強原有的通訊效率，提升傳輸效益和服務品質。為了因應效能提升，許多專門的技術油然而生，例如：多輸入多輸出(Multi-Input Multi-Output, MIMO)技術，可以在不增加頻寬或總傳輸功率的情況下增加系統的資料吞吐量以及服務的使用者人數；非正交多重存取(Non-Orthogonal Multiple Access, NOMA)技術，我們可以將多個使用者在功率域上疊加傳輸，並且在接收端使用連續干擾消除法逐一解碼訊號並消除部分干擾，達到提升服務品質(QoS)的目的。本文研究背景架構在於能夠最佳化選擇使用者的前提下，結合多輸入多輸出(MIMO)與非正交多重接取技術(NOMA)，使用預處理(Precoding)及後處理(Post processing)技術消除叢集干擾，探討系統吞吐量的最佳化，與不同的選擇使用者演算法比較分析結果，並且對所有使用者作功率分配，因此除了選擇到最佳用戶之外，也能根據最佳分配功率達到最高效率的傳輸。本論文所建立的系統原始數學模型為非凸非線性規劃問題，將藉由對數項的數學簡化來進行近似以及變數變換，利用疊代法(iteration)為基礎的連續凸逼近SCA(Successive Convex Approximation)演算法求得整個系統之最佳解。

In recent research of the wireless network research. As the popularity of the smart mobile device and the networking services of more devices, the demand for devices to access the Internet has gradually exceeded demand, amount of data transmitted are increasing rapidly. So that we must keep to update technology or strengthen the original communication Efficiency, improving the transmission efficiency and the quality of service (QoS).
In order to deal with the improvement of performance, many specialized technologies have emerged. Such as : Multi-Input Multi-Output (MIMO) technology, it can increase the data throughput of the system and the number of suitable user without increasing bandwidth or total transmission power ; Non-Orthogonal Multiple Access (NOMA) technology, At the transmitter, we perform superposition coding on power-domain so that the maximum bandwidth can be used for each user, and with the interference-cancellation technique, we can eliminate the interference to achieve the purpose of improving the quality of communication.
In this paper, we combine multiple input multiple output (MIMO) and non-orthogonal multiple access technology (NOMA) on the premise of selecting the best users, and use precoding and post-processing techniques to eliminate cluster interference. We discuss the optimization of system throughput, compares and analyzes the results of power allocation with different Algorithm for selecting users.
In addition, we can not only select the best user but the most efficient transmission be achieved according to the best allocated power. The original mathematical model of the system established in this paper is a non-convex non-linear programming problem, which will be approximated and transformed by the mathematical simplification of the logarithmic term, and obtained the best solution for the entire system by the SCA (Successive Convex Approximation) algorithm based on iterative method (iteration).

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