Dramco, ESAT-WaveCore, KU Leuven, 9000 Ghent, Belgium.
Sensors (Basel). 2023 May 23;23(11):4994. doi: 10.3390/s23114994.
Internet of Things technologies open up new applications for remote monitoring of forests, fields, etc. These networks require autonomous operation: combining ultra-long-range connectivity with low energy consumption. While typical low-power wide-area networks offer long-range characteristics, they fall short in providing coverage for environmental tracking in ultra-remote areas spanning hundreds of square kilometers. This paper presents a multi-hop protocol to extend the sensor's range, whilst still enabling low-power operation: maximizing sleep time by employing prolonged preamble sampling, and minimizing the transmit energy per actual payload bit through forwarded data aggregation. Real-life experiments, as well as large-scale simulations, prove the capabilities of the proposed multi-hop network protocol. By employing prolonged preamble sampling a node's lifespan can be increased to up to 4 years when transmitting packages every 6 h, a significant improvement compared to only 2 days when continuously listening for incoming packages. By aggregating forwarded data, a node is able to further reduce its energy consumption by up to 61%. The reliability of the network is proven: 90% of nodes achieve a packet delivery ratio of at least 70%. The employed hardware platform, network protocol stack and simulation framework for optimization are released in open access.
物联网技术为远程监控森林、田野等开辟了新的应用领域。这些网络需要自主运行：将超长距离连接与低能耗相结合。虽然典型的低功耗广域网具有远距离特性，但在提供超远程区域（跨越数百平方公里）环境跟踪覆盖范围方面存在不足。本文提出了一种多跳协议来扩展传感器的范围，同时仍能实现低功耗操作：通过采用长时间的前导码采样来最大化睡眠时间，并通过转发数据聚合来最小化每个实际有效负载位的传输能量。实际实验和大规模模拟证明了所提出的多跳网络协议的能力。通过采用长时间的前导码采样，当每 6 小时传输一次数据包时，节点的寿命可以延长到 4 年，而当连续侦听传入数据包时，寿命仅为 2 天，这是一个显著的改进。通过聚合转发的数据，节点可以进一步将其能耗降低多达 61%。网络的可靠性也得到了证明：90%的节点实现了至少 70%的数据包投递率。所使用的硬件平台、网络协议栈和用于优化的模拟框架都以开放获取的方式发布。
