Wireless Communication for High-reliability 2 Low-latency Control – Part I

High-performance industrial control systems with tens to hundreds of sensors and actuators have 9 stringent latency and reliability requirements. Current wireless technologies like WiFi, Bluetooth, LTE, 10 etc., are unable to meet these requirements, forcing the use of wired systems. This paper introduces 11 a wireless communication protocol framework, dubbed “Occupy CoW,” based on cooperative commu- 12 nication among nodes in the network to build the diversity necessary to deliver the target reliability. 13 Simultaneous retransmission by many relays achieves this without significantly decreasing throughput 14 or increasing latency. The key difficulty to overcome is the common knowledge of who needs to speak 15 what and when. 16 The protocol is analyzed using the communication theoretic delay-limited-capacity framework and 17 compared to baseline schemes that primarily exploit frequency diversity (including the practically 18 employed WISA). For a scenario inspired by an industrial printing application with 30 nodes in the 19 control loop, total information throughput of 4.8 Mb/s, and cycle time under 2 ms, an idealized protocol can achieve a system probability of error better than 10´9 20 with nominal SNR below 5 dB. We also 21 derive the probability of system failure for all cases.