Measurement-based analysis of adaptive relay selection in industrial wireless sensor networks

We evaluate by real-world measurements two cooperative relaying protocols for industrial sensor networks: the first one employs a periodic relay selection scheme, where relays are selected periodically from a candidate set at fixed time intervals, while the second one is an adaptive approach selecting relays depending on channel characteristics. We perform measurements of both protocols in a real-world industrial environment, and analyze and compare their performance characteristics in terms of frame delivery ratio and protocol overhead. Results show that the periodic protocol increases the frame delivery ratio considerably compared to direct transmission. Furthermore, the adaptive approach improves frame delivery even further. In particular, for cases where the frame error rate between source and destination is high, adaptive relaying improves frame delivery considerably beyond that of periodic relaying.