When a UAV broadcasts its location periodically during flight, a target will observe the strongest signal when the UAV is at the closest location; thus, the target can infer its location based on the observed signals and the UAV’s trajectory. We consider how to design trajectories for UAVs such that all targets can locate themselves, and the maximum length of trajectories is minimized. To make the problem tractable, we impose constraints on the set of possible trajectories such that they only contain the edges of small squares. We propose an integer-linear-programming-based solution, which runs in exponential time, and two polynomial-time constant-factor approximation algorithms. We implement a prototype system to verify the feasibility of the localization method. Simulations show that our approach outperforms the existing ones in terms of flight length and localization error.

中文翻译：

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最小化为地面目标提供定位服务的无人机的最大飞行路径长度


当无人机在飞行过程中定期广播其位置时，当无人机位于最近位置时，目标将观测到最强的信号；因此，目标可以根据观测到的信号和无人机的轨迹推断其位置。我们考虑如何设计无人机的轨迹，使得所有目标都能自我定位，并且轨迹的最大长度最小化。为了使问题易于处理，我们对可能的轨迹集施加约束，使它们仅包含小方块的边缘。我们提出了一种基于整数线性规划的解决方案，该解决方案在指数时间内运行，以及两种多项式时间常数因子近似算法。我们实现了一个原型系统来验证定位方法的可行性。模拟表明，我们的方法在飞行长度和定位误差方面优于现有方法。