在本文中，我們探討在多無人機 (UAVs) 網路中上行傳輸的問題。每架無人機將根據所設計的飛行中心、高度和半徑，在負責區域上空動態地飛行，並收集地面設備之數據。我們的目標是最大化減少設備的總傳輸功耗。首先，給定無人機的飛行高度，我們使用動態規劃 (DP) 方法，通過考慮設備的流量需求和無人機的容量限制，將設備分配給適當的無人機服務。接下來，我們使用內點法調整無人機的飛行高度，以進一步最大化減少設備的總傳輸功耗。模擬結果顯示，我們所提出的演算法在總節省傳輸功率方面優於候選演算法。

In this work, we study the multiple unmanned aerial vehicles (UAVs) for uplink transmission in a network. Each UAV is assumed to dynamically hover over the responsible region with a designed flying center, altitude, and radius to collect the data from ground devices. Our objective is to maximize the total saved transmission power of devices compared to the ones using the maximum transmission power to transmit data to UAVs. First, given a flying altitude of UAVs, we use dynamic programming (DP) approach to assign a device to an appropriate UAV by considering the traffic demand of devices and the capacity limitation of UAVs. Next, we use interior-point method to adjust the flying altitude of UAVs to further maximize the total saved transmission power of devices. The simulation results show that the proposed algorithms outperform the candidate algorithms in terms of the total saved transmission power.

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