基于无人机群和D2D的空地协同多跳通信是空地一体化网络研究的前沿热点问题，无人机群空间位置多变、通信链路复杂、信道质量差异大、飞行约束条件多等因素使得空地协同多跳网络在网络拓扑、协同传输、频谱分配、干扰管理、用户QoS保障领域面临新挑战。现有研究大多考虑基于单架无人机或一跳D2D的简单场景，其方法不适用于空地协同多跳网络。鉴于此，本项目拟结合随机几何等理论工具，研究基于接收信号强度（RSS）优先级的无人机群空地信道接入机制；针对多跳链路的协同问题，研究基于RSS阈值的用户传输模式选择方法；建立数学模型刻画空地协同多跳链路的随机动态建立过程，解析网络覆盖率、平均可达速率等性能指标；给出无人机群和D2D通信频谱资源分配及RSS阈值配置最优化方案。本项目的实施，可为未来基于无人机群和D2D多跳通信组网设计和优化打下必要的理论基础，并为其在空天地一体化网络以及物联网的广泛应用提供理论和技术支持。

The air-ground cooperative multi-hop network based on UAV fleet and D2D communications (AGCMN) has become a hot topic of discussion on the air-ground integrated networks. Important issues like the changing location, complex communication links, different channel quality, and various flight restrictions, will bring new technical challenges to AGCMN in the fields of interference management, network topology, spectrum allocation, cooperative transmission, QoS guarantee. Furthermore, as the existing theoretical research results of the air-ground networks based on single UAV or single-hop D2D cannot apply, the actual achievable performance of AGCMN remains unknown. Towards this end, we aim to utilize available theoretical tools like stochastic geometry, etc., to develop the channel access mechanisms for the establishment of UAV fleet links according to the priority-based received signal strength (RSS); to develop the transmission mode selection mechanism regarding the cooperation of multi-hop links based on RSS threshold; to characterize the complicated dynamics experienced establishment of multi-hop links based on UAV fleet and D2D communications; to derive the basic performance metrics such as coverage rate and average rate; to further study the optimum schemes in terms of spectrum allocation and RSS threshold configuration. The successful implementation of this project, is able to establish the fundamental basis for the design and optimization of future networks based on UAV fleet and D2D communications, and to provide both theoretical and technical support for their applications in future space-air-ground integrated networks and Internet-of-Things.