Achieving ultra-high reliability for short packets is a core challenge for future wireless communication systems, as current systems are designed only to transmit long packets based on classical information-theoretic principles. To tackle this challenge, this letter relies on multi-hop unmanned aerial vehicle (UAV) relay links to deliver short ultra-reliable and low-latency (URLLC) instruction packets between ground Internet of Things (IoT) devices. To accomplish this task, we perform non-linear optimization to minimize the overall decoding error probability in order to find the optimal values of the distance and the blocklength. In this vein, a novel, semi-empirical based non-iterative algorithm is proposed to solve the quasi-optimization problem. The algorithm executes in quasilinear time and converges to a globally optimal/sub-optimal solution based on the chosen parameters. Simulation results demonstrate that our algorithm allows operation under the ultra-reliable regime (URR), and yields the same performance as exhaustive search algorithms.

中文翻译：

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URLLC辅助多跳无人机中继链路中距离和块长度的准优化

实现短数据包的超高可靠性是未来无线通信系统的核心挑战，因为当前系统仅设计用于基于经典信息论原理传输长数据包。为了应对这一挑战，这封信依靠多跳无人机 (UAV) 中继链路在地面物联网 (IoT) 设备之间传递短的超可靠和低延迟 (URLLC) 指令数据包。为了完成这项任务，我们执行非线性优化以最小化整体解码错误概率，以便找到距离和块长度的最佳值。在这方面，提出了一种新颖的、基于半经验的非迭代算法来解决准优化问题。该算法在拟线性时间内执行，并根据所选参数收敛到全局最优/次优解。仿真结果表明，我们的算法允许在超可靠机制（URR）下运行，并产生与穷举搜索算法相同的性能。