近年來隨著無線通訊技術的進步與行動式裝置的普及化，人們對於頻寬效益與功率效益的要求日漸提升，而伴隨著第五代(5G)行動通訊網路的到來，在發展新技術的同時並結合舊有的技術來思考如何在有限的頻寬下增加通道效益以滿足所需的服務品質(Quality of Service, QoS)。在現今的網路研究中，多輸入多輸出(Multi-Input Multi-Output, MIMO)技術與非正交多重擷取(Non-Orthogonal Multiple Access, NOMA)技術在近幾年是受到相當大的矚目，多輸入多輸出技術可以在不需要增加頻寬或總傳輸功率的情況下來增加系統的資料吞吐量及傳送距離，而非正交多重擷取技術可以將所有使用者的訊號線性疊加在一起發送，利用整個系統的頻寬同時服務所有使用者，並在接收端使用連續干擾消除(Successive Interference Cancellation, SIC)解碼技術逐一解碼並消除部分干擾，上述兩種技術的目的都是為了提升系統服務品質。
本文研究背景在單一細胞網路架構的下行傳輸，使用多輸入多輸出-非正交多重擷取(MIMO-NOMA)傳輸方式並在發送端採用最大比例合併(Maximum Ratio Combining, MRC)預編碼技術並將使用者分為等同基地台發送天線數量的叢集(Cluster)，叢集內的使用者共享同個波束形成向量，並探討系統吞吐量之最佳化。由於本文所建立的原始數學模型為非凸(Nonconvex)非線性規劃(Nonlinear Programming)問題，藉由piecewise-RLT、大M法則以及對數項的數學近似對原始數學模型進行線性放鬆，最後利用CPLEX之分枝切割法(Branch and cut)求得系統的最佳解並分析結果。

In recent years, with the advancement of wireless communication technology and the popularization of mobile devices, people's requirements for bandwidth efficiency and power efficiency are increasing day by day. With the advent of the fifth generation mobile communication network, while developing new technologies and combined with the old technology to think about how to increase the channel efficiency under the limited bandwidth to meet the required Quality of Service. In today's network research, MIMO technology and Non-Orthogonal Multiple Access (NOMA) technology have received considerable attention in recent year. The background of this paper is the downstream transmission of a single-cell network, using MIMO-NOMA transmission method and the MRC precoding technology at the transmitter. The users are divided into clusters equal to the number of base station transmit antennas. The users in the cluster share the same beamforming vector. Since the original mathematical model established in this paper is a non-convex nonlinear programming problem, it is linearly relaxed by piecewise-RLT、big M method、mathematical approximation of logarithmic terms, and the branch and cut algorithm of CPLEX , then we can finally find the optimal solution of the system.

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