SoLiCiT: Synchronous Listen, Code, and Transmit Protocol for Wireless Control Applications

Abstract

Industrial control applications are deployed in environments characterized by high signal attenuation and severe multipath fading, which is a potential cause for significant packet losses. This is in conflict with achieving low latency and highly reliable wireless communication, a requirement of closed-loop control applications. We propose SoLiCiT, a wireless networking protocol that employs concurrent transmissions with specifically designed erasure coding to meet these demands without the need for retransmissions. Synchronous transmissions help to realize a simple protocol design while using helper nodes to transmit redundancy allows for lost packets to be recovered within fixed and tight latency bounds. We provide a range of coding solutions that can be tailored to the application and also present a case study with a battery storage management application in which battery cells report their status to a central management unit. Using a realistic ray tracing model of the actual battery storage container, we evaluate the radio environment and show the efficacy of SoLiCiT compared to benchmarking schemes, such as a low-power wireless bus.