行動網路在近年來發展迅速使得人們無論在何時何處都能上網接收網路上的資訊，也因為如此，行動裝置也越來越流行，幾乎是人人都有一台。因此，行動網路中傳送的資料量也呈現爆炸性成長，單靠原先的傳統大基地台(Macro)已經無法負荷，因此在大基地台下新增小型基地台來補強較邊緣的位置或是用戶較多的地區，來加強用戶的服務品質，而在此異質性網路下本論文在大、小基地台之間可以藉由多點協調傳輸資料來更加強在基地台邊緣用戶的服務品質。而這幾年第五代行動通訊網路仍在研究當中，而其中非正交多重接取(NOMA)是其主要技術，本論文將NOMA運用在基地台傳輸之中，以提高用戶更好的服務品質。本篇論文建立此網路架構探討系統吞吐量的優化，其中網路的原始數學模型為非線性規劃問題，藉由piecewise-RLT以及對數項目的近似之數學技巧，將原始模型轉換成混合整數線性規劃問題，最後使用C++結合CPLEX來進行模擬，得到整個模型的最佳解。

Mobile networks have grown rapidly in recent years. This allows people to receive information on the Internet whenever and wherever they want. Mobile devices are also becoming more and more popular, almost everyone has one. Therefore, the amount of data transmitted in the mobile network is also exploding. The original traditional Marco base station is unable to load. Therefore, a small base station is added under the Marco base station to reinforce the marginal location or the area with more users. small base station can enhance the quality of service of users. In heterogeneous networks, the communication quality of users at the edge of the base station can be further enhanced by coordinated multipoint transmission of data between large and small base stations. The fifth generation mobile communication networks still study in recent years. Non-orthogonal multiple access (NOMA) is its main technology. We use NOMA in base station transmission to improve users' better service quality. This paper establishes this networks architecture to explore the optimization of system throughput. The original mathematical model of the network is a nonlinear programming problem. Converting the original model into a mixed integer linear programming problem by piecewise-RLT and logarithmic approximation. Finally, using C++ combined with CPLEX to simulate, we can find the optimal solution of the model.

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