現今，無人機（UAV）輔助無線通信網絡已成為熱門話題。然而，如何有效地擴展無人機網絡的有限覆蓋區域仍然是一個重要的問題。在這個研究中，我們開發了一種多觸手 D2D 網絡（MTDN）來實現這個目標。具體來說，整個 MTDN 由幾個部分組成，包括非正交多接入（NOMA）空對地配對、無人機定位、地面設備的集群、鏈路選擇和傳輸功率控制。為了服務地面上分布廣泛的設備，需要精心設計集群算法和適當的無人機位置，以便可以應用設備對設備（D2D）的傳輸方案來有效地擴大無人機輔助網絡的覆蓋範圍。此外，為了提高整體傳輸速率，應良好地選擇 NOMA 空對地配對以及 D2D 傳輸鏈路。此外，應適當地控制選定鏈路的傳輸功率，以便成功抑制同時傳輸產生的干擾。模擬結果已驗證了該方案在擴大覆蓋區域和提高無人機輔助網絡的傳輸速率方面的有效性。

Nowadays, the unmanned aerial vehicle (UAV) assisted wireless communication network has become a hot topic. However, how to effectively extend the limited coverage area of the UAV network is still an important issue. In this study, we develop a multi-tentacle D2D network (MTDN) to achieve this goal. Specifically, the overall MTDN consists of several components, including the non-orthogonal multiple access (NOMA) air-to-ground pairs, positioning for UAV, clustering for ground devices, link selection and transmission power control. In order to serve the widely spread devices on the ground, the clustering algorithm together with a proper position for UAV should be carefully designed such that the device-to-device (D2D) transmission scheme can be applied to effectively extend the coverage of the UAV assisted network. Also, to boost the overall transmission rate, the NOMA air-to-ground pairs as well as the D2D transmission links should be well selected. Moreover, the transmission power of the selected links should be properly controlled so that the interference caused by the concurrent transmissions can be successfully suppressed. The simulation results has verfied the effectiveness of the proposed scheme in extending the coverage area and raising the transmission rate for the UAV assisted network.

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