Internet of Things (IoT) involves sensors for monitoring and wireless networks for efficient communication. However, resource-constrained IoT devices and limitations in existing wireless technologies hinder its full potential. Integrating Unmanned Aerial Vehicles (UAVs) into IoT networks can address some challenges by expanding its' coverage, providing security, and bringing computing closer to IoT devices. Nevertheless, effective data collection in UAV-assisted IoT networks is hampered by factors, including dynamic UAV behavior, environmental variables, connectivity instability, and security considerations. In this survey, we first explore UAV-based IoT networks, focusing on communication and networking aspects. Next, we cover various UAV-based data collection methods their advantages and disadvantages, followed by a discussion on performance metrics for data collection. As this article primarily emphasizes reliable and efficient data collection in UAV-assisted IoT networks, we briefly discuss existing research on data accuracy and consistency, network connectivity, and data security and privacy to provide insights into reliable data collection. Additionally, we discuss efficient data collection strategies in UAV-based IoT networks, covering trajectory and path planning, collision avoidance, sensor network clustering, data aggregation, UAV swarm formations, and artificial intelligence for optimization. We also present two use cases of UAVs as a service for enhancing data collection reliability and efficiency. Finally, we discuss future challenges in data collection for UAV-assisted IoT networks.

翻译：物联网涉及用于监控的传感器和用于高效通信的无线网络。然而，资源受限的物联网设备及现有无线技术的局限性阻碍了其潜能的充分发挥。将无人机集成到物联网网络中可以解决部分挑战，包括扩大覆盖范围、提供安全保障、以及将计算能力靠近物联网设备。尽管如此，无人机辅助的物联网网络中的数据采集仍受到动态无人机行为、环境变量、连接不稳定性和安全因素等多方面制约。本综述首先探讨基于无人机的物联网网络，重点关注其通信与组网特性；随后梳理多种无人机数据采集方法的优劣，并讨论数据采集的性能指标。由于本文重点强调无人机辅助物联网网络中可靠高效的数据采集，为深入理解可靠数据采集的内涵，我们简要回顾了现有关于数据准确性与一致性、网络连接性、以及数据安全与隐私的研究。此外，我们探讨了无人机物联网网络中高效数据采集策略，涵盖轨迹与路径规划、碰撞避免、传感器网络聚类、数据聚合、无人机群组编队以及用于优化的人工智能技术。本文还通过两个无人机即服务的用例，展示如何提升数据采集的可靠性与效率。最后，我们讨论了无人机辅助物联网网络中数据采集的未来挑战。