隨著無線行動裝置和多媒體系統的蓬勃發展，人們對於網路服務的需求量與日俱增，但是由於頻寬資源有限，學者開始研究新的通訊技術來提升通道效益(Channel Efficiency)，進而讓相同成本下的通訊系統可以為更多的使用者服務。非正交多重接取(NOMA)已經證實將在5G系統中當作研究對象。根據多項研究指出，我們預期在接收端使用NOMA with Successive Interference Cancellation(SIC)可以在通道效益與使用者公平性(user fairness)之間取得更好的平衡。並且，為了提供細胞邊緣(cell edge)使用者更好的服務品質，學者另外提出Cooperative NOMA，將以往的多點協調傳輸(CoMP)，也就是合作式通訊系統架構加入NOMA with SIC，藉此讓功率分配更加彈性。在本篇論文中，我們將基於使用者吞吐量最大化最小公平性(Maxmin fairness)這項最佳化問題，探討Cooperative NOMA、NOMA與其他傳統網路架構在系統公平性之效能。由於原始模型為非凸(non-convex)非線性規劃問題(Non-Linear Programming)，為NP-HARD問題。我們利用對數項之近似、piecewise-RLT等方式使得原始模型可以被求解，最後利用CPLEX求解軟體求出最佳解並分析結果。

In this study ,we investigates a power allocation problem for maximizing the minimum achievable users’ throughput in downlink coordinated multipoint(CoMP) with non-orthogonal multiple access (NOMA) using successive interference cancellation (SIC).First, non-orthogonal multiple access (NOMA) is one of the promising candidates in 5G system. NOMA offer a set of benefits, including great channel gain and spectrum efficiency. Second, we combine CoMP in able to enhance the quality of service for the Cell edge user in Heterogeneous Network. The original mathematical model of the network is a nonlinear programming problem. Converting the original model into a mixed integer linear programming problem with piecewise-RLT and mathematical approximate skills of the logarithmic term. Finally, using C++ combined with CPLEX to simulate, get the best solution of the whole model.

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