A Graph Route-Based Superframe Scheduling Scheme in WirelessHART Mesh Networks for High Robustness

WirelessHART is considered to be one of the most promising wireless network protocols for its high robustness comparing to other similar wireless networks. The high robustness comes from its unique routing protocol and redundant superframe scheduling scheme. This paper focuses on the time-slot scheduling and channel assignment of WirelessHART and a graph route-based superframe scheduling scheme is proposed. In order to improve the communication reliability, our scheme applies hop-level retransmission mechanism in a multi-hop and multi-channel circumstance. Moreover, time-slot conflict and channel interference are considered and an effective solution strategy is proposed. To meet the real-time communication requirements, time-slots are assigned in the order of actual communication sequence which can effectively reduce the retransmission delay. Further more, we propose the implementation algorithm of our scheme. The performance analysis shows that our scheduling scheme has a higher robustness than the traditional non-redundancy scheme.