In this paper, we propose an uplink multiuser-multiple input multiple output (MU-MIMO) cooperative retransmission control scheme for the reliable and efficient communication of autonomous unmanned aerial vehicles (i.e., flight communication and drone-to-drone communication). This scheme is a key element in the design of a drone-based ad-hoc network. Because drone relay transmission operates in the air, flexible wireless relay networks over large areas can be achieved without interference from multipath signals caused by buildings and obstacles in ground-based communication. However, two main challenges exist. First, the relay transmission system occupies bandwidth every time the drone relays information. Therefore, because the radio channel is shared by multiple relay stations, the throughput is greatly reduced. To improve throughput, it is better to transmit using the minimum number of relay stations. Ultimately, long-distance direct transmission is the best. The other issue is a direct result of the first issues solution: the propagation loss increase when relaying information directly over a long distance. Moreover, because the frequency of interference waves from the ground increases, transmission signal errors are an important issue. To solve this issue, a transmission scheme to reduce errors is required. The scheme proposed in this study achieves high transmission reliability and efficiency even under high transmission error conditions. The results of a computer simulation reveal that the proposed method achieves a direct transmission throughput that is 1.5 times better than that of a conventional scheme. It is also shown that the proposed scheme requires only about three stations to achieve acceptable results.

中文翻译：

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基于无人机的网络中的协作传输方案

在本文中，我们提出了一种上行链路多用户多输入多输出（MU-MIMO）协作重传控制方案，用于自主无人机的可靠高效通信（即飞行通信和无人机对无人机通信）。该方案是设计基于无人机的自组织网络的关键要素。由于无人机中继传输在空中进行，因此可以实现大面积灵活的无线中继网络，而不受地面通信中建筑物和障碍物引起的多径信号的干扰。然而，存在两个主要挑战。首先，中继传输系统每次无人机中继信息都会占用带宽。因此，由于无线信道被多个中继站共享，吞吐量大大降低。为了提高吞吐量，最好使用最少数量的中继站进行传输。最终，长距离直接传输是最好的。另一个问题是第一个问题解决方案的直接结果：直接长距离中继信息时传播损耗增加。此外，由于来自地面的干扰波频率增加，传输信号错误是一个重要问题。为了解决这个问题，需要一种减少错误的传输方案。本研究中提出的方案即使在高传输错误条件下也能实现高传输可靠性和效率。计算机仿真结果表明，所提出的方法实现的直接传输吞吐量是传统方案的 1.5 倍。