Towards Tactile Wireless Multi-Hop Networks : The Tactile Coordination Function as EDCA Supplement

Most studies covering the Tactile Internet focus on single-hop wireless applications, but 5G/B5G scenarios like robot and Machine-to-Machine communication (e.g., mars missions), and Device-to-Device networks also require multi-hop communication. We study and propose a Tactile Coordination Function (TCF) to complement the Medium Access Control (MAC) layer of the IEEE 802.11 standard. It introduces a new Access Category (AC) designed specifically for haptic data streams. TCF reduces latency and jitter while being fully backward-compatible with the existing Hybrid Coordination Function (HCF) in IEEE 802.11. We achieve 1 ms end-to-end latency in three-hop wireless networks, which is one of the main requirements for haptic applications. Although latency and jitter do not exactly increase linearly with the hop count, they both behave invariant to background traffic.