Supporting Ultralow-Power Nodes in 6TiSCH Industrial Wireless Sensor Networks

Industrial wireless sensor networks offer a viable alternative to wired solutions where there is a lack of suitable communication infrastructure. Among these networks, time slotted channel hopping (TSCH) emerges as a noteworthy choice due to its capacity for deterministic latency, heightened reliability, and low power consumption. Nonetheless, challenges arise from the energy-intensive joining procedure and inherent idle listening associated with TSCH, impeding the integration of battery-powered end devices. Therefore, this article introduces a novel 6TiSCH low-power node (6LPN) that supports ultralow-power operations. The proposed solution optimizes the energy-intensive joining procedure through reduced advertisement channels, optimal scanning time, and a delayed join, achieving a 90% reduction in energy consumption. Furthermore, idle listening is eliminated by queueing downlink traffic in a 6TiSCH friend node (6FN), ensuring an 87%-94% reduction in power consumption during operational mode while maintaining an average latency of queued frames of 7.62 s. By comparing the impact of the optimizations on three Internet of Things (IoT) hardware platforms, we demonstrate that optimal results are obtained for devices with low RX and idle transceiver current. Finally, our solution maintains full backward compatibility with 6TiSCH and does not introduce additional control traffic.