无人机联合D2D应急通信网络的性能分析

无人机与D2D(device-to-device)通信技术相结合可作为应急通信网络的可行选项之一，但存在复杂的同频干扰问题。为了降低干扰，提出一种无人机配备定向天线阵列的网络。以系统内用户作为主要研究对象，利用随机几何理论，对所提网络进行系统建模，将D2D通信用户以及无人机通信用户建模为两个独立分布的齐次泊松点过程，推导了D2D用户成功传输概率的精确表达式以及无人机通信用户成功传输概率的上下界理论表达式。仿真结果验证了理论公式的准确性，且相比全向天线，无人机配备定向天线可以有效地提高网络性能。同时，存在最优的无人机高度以及密度，使系统和速率最大化。

Performance analysis of UAV joint D2D emergency communication networks

The coexisting network of unmanned aerial vehicles (UAV) and D2D communication can be one of the viable options for emergency communication network. Limited by spectrum resources, UAV and D2D users tend to share spectrum, which leads to increased interference link network, affecting the communication performance of the network. Therefore, directional antenna was adopted to be equipped on UAVs to reduce the interference impact. To quantitatively analyze its specific impact on the network, stochastic geometry was adopted to model the proposed network and derive the analytical expressions of the successful transmission probabilities for D2D users and UAV users. Then, the impacts of key parameters such as the UAV density and the antenna array size on the system performance were discussed. The simulation results show that, compared with omnidirectional antennas, UAV with directional antenna can effectively improve network performance, and there is an optimal density of UAVs that maximizes the successful transmission probability of UAV users.