隨著網路技術發展個人行動裝置的數量隨之提升，反映出人們對網路的需求的提升，伴隨而來是資料傳輸需求增加，使我們必須不斷發展新技術，或將舊技術結合來達到更高的傳輸量。而近年來5G網路研究中，有兩項技術是具有發展性的第一是非正交多重存取(Non-Orthogonal Multiple Access, NOMA)技術，我們可以將多個使用者在功率域上疊加編碼傳輸，每位使用者能夠利用最大的頻寬，並且在接收端使用串行干擾消除法(Successive interference cancellation, SIC) 逐一解碼訊號並消除部分干擾，達到提升服務品質的目的；第二是多輸入多數出（Multi-input Multi-output, MIMO）技術，在發送端跟接收端都使用了多根的天線各自獨立的傳輸與接收訊號，這樣的做法可以增加對於通道的描述並且大大提升還原該信號的能力。本文研究背景架構在單一細胞網路，藉由一個基地台服務多個使用者，結合非正交多重接取技術(NOMA)和多輸入多數出技術(MIMO)中的預編碼矩陣，探討系統吞吐量的最佳化，對使用者數量及相互之間的距離比較分析。本論文所建立的網路系統原始模型為非線性規劃問題，藉由piecewise-RLT及對數項的數學簡化來進行線性放鬆，並且利用CPLEX之分枝切割法(Branch and cut)求得整個系統的最佳解。

With the development of network technology, the number of personal mobile devices has increased, reflecting the slow increase in people's demand for the network, accompanied by the increase in data transmission needs, so that we must continue to develop new technologies or combine old technologies Achieve higher throughput. In recent years, there are two technologies that are developmental in 5G network research. The first is non-orthogonal multiple access (Non-Orthogonal Multiple Access, NOMA) technology. We can superimpose multiple users on the power domain. For transmission, each user can use the maximum bandwidth and use serial interference cancellation (SIC) at the receiving end to decode signals one by one and eliminate some of the interference to achieve the purpose of improving service quality; the second is Multi-Input Multi-Output (MIMO) technology uses multiple antennas to transmit and receive signals independently at the sending end and the receiving end. This method can increase the description of the channel and greatly improve the restoration of the signal. This paper studies in a single cell network, serving multiple users with one base station, combining non-orthogonal multiple access technology (NOMA) and precoding matrix in multi-input multiple output technology (MIMO), to explore the optimal system throughput , a comparative analysis of the number of users and the distance between them. The original model of the network system established in this paper is a non-linear programming problem. It is linearly relaxed by piecewise-RLT and the mathematical simplification of the logarithmic term, and the branch and cut method of CPLEX is used to obtain the best solution of the entire system.

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