灾后应急通信网络下的中继选择与轨迹优化研究

Research on Relay Selection and Trajectory Optimization in Post-disaster Emergency Communication Network

近年来,无人机(UAVs)凭借其机动灵活的特点,广泛应用于灾后救援工作。针对灾后应急通信网络下勘察无人机执行任务的场景,为了延长应急通信网络的整体续航时间,该文考虑了中继无人机的可用通信能量以及勘察无人机的最大飞行速度和实时通信质量,通过联合优化中继选择和飞行轨迹来实现系统的能量效率最大化。对于所涉及的非确定性多项式难度(NP-hard)优化问题,该文提出一种基于连续凸近似和禁忌搜索的交替迭代算法,将原问题拆成两个子问题交替求解,得到优化问题的近似最优解。仿真结果表明,该文所提算法具有较好的收敛性,可以有效提高系统的能量效率,相比于只优化中继和只优化轨迹的基准方案,能够提升31.1%和28.2%的性能。

In recent years,Unmanned Aerial Vehicles(UAVs)have been widely used in post-disaster rescue by virtue of their mobility and flexibility.Considering the scenario that a survey UAV performs tasks using the emergency communication network,in order to extend the overall endurance of the emergency communication network,in this paper,the energy efficiency of the system is maximize by jointly optimizing the relay selection and flight trajectory of the UAV.In addition,the available communication energy of the relay UAVs as well as the maximum flight speed and real-time communication quality of the survey UAV are also considered in the optimization.The resultant Nondeterministic Polynomial hard(NP-hard)optimization problem is approximately solved using an alternate algorithm,which consists of successive convex approximation and tabu search algorithm.The alternate algorithm splits the original problem into two subproblems and solves them alternately to obtain the approximate optimal solution of the optimization problem.Simulation results show that the proposed algorithm has a desirable convergence and can significantly improve the energy efficiency of the system.The performance of the proposed algorithm is improved by 31.1%and 28.2%compared to the benchmark schemes of relay or trajectory optimization.