Reliable Industrial Wireless Operations through Adaptively Filtered Time-slotted Channel Hopping

ABSTRACT High-performance industrial wireless applications have stringent requirements on communication latency and reliability. However, current wireless technologies are vulnerable to external interference, being faced with the dilemmas of unpredictable delays and unacceptable quality of service (QoS). Therefore, some recent well-proven protocols focus on the time-slotted channel hopping (TSCH) technology for lossy wireless channels, which can achieve highly-reliable and low-power networking by scheduling and switching to the stable channels. However, it is still difficult to apply time slotting to dynamic networks as envisioned in the industrial internet of things (IIoT). In this paper, we model the interference pattern in dynamic and harsh industrial networks and design heuristics to filter the low-qualified channels. We enable the transmitter and the receiver to reach a consensus on the filtered channels so as to prevent the deafness problem. Moreover, we also propose a rebound scheme to recover the filtered channels so as to adapt to the dynamic environments. We demonstrate the practicality of the proposed algorithm and quantify the benefits through extensive experiments. Experiment results show that the proposed algorithm can increase the packet delivery rate by 12% for the unstable links.