WLC12-5: A TDMA-Based MAC Protocol for Industrial Wireless Sensor Network Applications using Link State Dependent Scheduling

Existing TDMA-based MAC protocols for wireless sensor networks are not specifically built to consider the harsh conditions of industrial environments where the communication channel is prone to signal fading. We propose a TDMA-based MAC protocol for wireless sensor networks built for industrial applications that uses link state dependent scheduling. In our approach, nodes gather samples of the channel quality and generate prediction sets from the sample sets in independent slots. Using the prediction sets, nodes only wake up to transmit/receive during scheduled slots that are predicted to be clear and sleep during scheduled slots that may potentially cause a transmitted signal to fade. We simulate our proposed protocol and compare its performance with a general non-link state dependent TDMA protocol and a CSMA protocol. We found that our protocol significantly improves packet throughput as compared to both the general non-link state dependent TDMA protocol and CSMA protocol. We also found that in conditions which are not perfect under our assumptions, the performance of our protocol degrades gracefully.