With the deep integration of information, communication and operation technologies, industrial wireless control networks (IWCNs) are playing key roles to drive industrial revolution. This article proposes a 5G-based new radio (NR) for IWCNs to realize ultra-reliable low-latency communication over unlicensed bands, namely WIA-NR. We first define a hierarchical star network topology, which employs a hybrid centralized and distributed system management architecture. Then, a three-layer protocol stack is defined by integrating some fundamental functions of 5G and proposing new functions to enhance reliability and timeliness. The key technologies include dynamic multi-channel listen before talk, adaptive channel hopping, over-the-air time synchronization, industrial data priority scheduling, aggregation and disaggregation. Finally, system-level simulations are performed to evaluate the performance of WIA-NR. The results show that WIA-NR can achieve less than 1 ms latency under 99.999 percent reliability constraint, which can well satisfy critical industrial control. Meanwhile, WIA-NR can harmoniously coexist with WiFi over unlicensed bands.
This work is published on IEEE NETWORK 35.1(2021):258-265.