NIST Reports that IEEE 802.11 OFDMA Frame Triggering Could Improve Latency for Time-critical Applications Using Wireless

Rick Candell of the NIST Communications Technology Laboratory (CTL) presented research findings at the International Conference on Advance Intelligent Mechatronics in Boston on July 17, 2024, on the current efficacy of IEEE 802.11ax Orthogonal Frequency Division Multiple Access (OFDMA) technology for use in time-critical applications. In the paper, “Latency-Sensitive Networked Control Using 802.11ax OFDMA Triggering,” Dr. Candell and his team reported that, while OFDMA has promise to support real-time deterministic communications capability for closed-loop robotic control, currently available devices must place more emphasis on supporting time-critical applications by providing users with parameter adjustment of the OFDMA frame triggering algorithm. Such control would allow for reduced latency and improved assurance that transmission deadlines are met. Currently, device manufacturers successfully design OFDMA implementations to support downlink traffic applications such as video download for multiple users in home and office environments. Typical 802.11 implementations focus more on data throughput rather than meeting transmission deadlines. Robotic control, safety, and other industrial applications are normally very uplink intensive, requiring low latencies rather than high throughput. The NIST team plans to focus efforts to better understand the performance gaps in the ubiquitous 802.11 technology to support the growing demand of wireless communications for controls.