Further Enhanced URLLC and Industrial IoT support with Release-17 5G New Radio
11 January 2022
The 5G New Radio (NR) standard has been designed since its initial release, 3GPP Release 15, to support Ultra-Reliable Low-Latency Communications (URLLC) requiring one-way downlink (DL) or uplink (UL) user-plane latencies of 1 ms with reliability of at least 99.999%. The following releases, Release 16 and 17, have further raised the bar not only by offering further reduced latencies down to 0.5 ms and increased reliability up to 99.99999%, but also by supporting new Industrial Internet of Things (IIoT) use cases demanding - among other things - time synchronization with 1 µs accuracy. This article provides an overview of the latest IIoT and URLLC-related enhancements adopted in the 5G NR standard, with focus on the recently standardized Release 17 features. This includes enhancements to the Hybrid Automatic Repeat Request (HARQ) and Channel Quality Indicator (CQI) feedback from the UE, propagation delay compensation for more accurate time synchronization, reliability and latency enhancements tailored to deployments on unlicensed bands, and scheduling optimizations taking into account different traffic priorities and higher-layer requirements of the industrial applications. Example performance results show how NR Release 17 offers improved performance over a wider range of deployment scenarios and frequency bands. Finally, an outlook towards expected URLLC and IIoT enhancements in future releases is provided.
