此篇論文中，我們考慮了一個高密度的網路環境，由於災難，地面基站無法運作。所以我們部署了一架無人機來提供緊急通信服務。並且我們提出了一種通過D2D 傳輸擴展無人機覆蓋範圍的演算法，選出適當的簇頭（CH）負責當作D2D 觸手網路之起點，延伸至無人機覆蓋範圍外之設備。
此外，為了提升整體系統表現，我們運用了非正交載波多工(NOMA)技術。其中的CH 配對問題，我們提出了一個低複雜性算法解決了NOMA 的配對問題。然而，由於在同一個D2D 網路和配對之D2D 頻譜共享緣故，設備間干擾會嚴重影響系統效能。因此在本文最後，我們提出了一個共同路徑選擇與功率控制演算法來選出並調配合裡的傳輸功率，以達到更高的通訊速率和以及無人機之覆蓋率。

It's no secret that 5G has a great impact on our daily lives. High-speed and stable transmission can not only make our lives more convenient but also make rescue operations more immediate. In this paper, we considered an area where the ground BS break down due to some disasters, so we deployed an UAV to provide a real-time cellular network. To extend UAV coverage and enhance the usage effectiveness of channel frequency , we apply Non-Orthogonal Multiple Access (NOMA) and Device to Device (D2D) technology into UAV wireless system. Furthermore, this paper jointly maximizes the total sum rate and power control for interference alleviation. We also propose an algorithm for CH selection , routing path selection , power control, and user pairing. At last, we nd an optimal power control strategy that not only makes the interference alleviation but also maximizes the total sum rate.

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