在本文中，我們通過構建多觸角D2D網絡來研究高密度無人機（UAV）輔助網絡的覆蓋範圍擴展方案。為了有效地管理高密度網絡，必須對地面設備進行分群並且為每個簇頭（CH）分配一個正交信道來促進網絡管理的便利性。在這種情況下，最重要的問題是要讓每個CH可以為無人機覆蓋範圍之外的設備（即我們所說的多觸角D2D網絡）建立一條多跳路由路徑。但是，由於每個群集內的頻譜共享，可能導致非常嚴重的群集內干擾。為了減輕這種干擾，對於從已開發的路由路徑中選擇合適的鏈路，並且適當調整此鏈路的傳輸功率。利用這種方式的，可以實現更高的系統總吞吐量和覆蓋概率。

In this paper, we investigate the coverage extension scheme for the high-dense unmanned aerial vehicle (UAV) assisted network by constructing the multi-tentacle D2D network. To well manage the high-dense network, the clustering for the ground devices becomes necessary; and allocating each cluster-head (CH) an orthogonal channel can facilitate the network management as well. On top this scenario, each CH can develop a multi-hop routing path for the devices outside the coverage area of the UAV (i.e., what we called the multi-tentacle D2D network). However, owing to the spectrum sharing within each cluster, the stringent intra-cluster interference can be incurred. To alleviate this kind of interference, the transmission power is properly adjusted for the well-selected links from the developed routing paths. In this fashion, the higher overall throughput and coverage probability can be achieved.

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