Reliable And Energy Efficient Routing Algorithm And Scheduling For Wirelesshart

WirelessHART is the first open-standard wireless communication protocol designed for industrial automation and process. The WirelessHART standard uses TDMA and channel hopping techniques to control access of the network and to communicate between network devices. Compared with the decentralized control adopted by wireless ad-hoc or peer-to-peer networks, WirelessHART advocates explicit and centralized network management for reliable and real-time network communication. Before WirelessHART is released, there have been a few publicly available standards on office automation, such as ZigBee and Bluetooth. However, these technologies cannot meet the stringent requirements of industrial applications.Different from the star network or the tree network in which the transmissions always use the fixed links, the topology of WirelessHART is a mesh network in which data can be transmitted (or retransmitted) along different paths. Due to the existence of multi-path routing between Mesh nodes, the network has a strong fault-tolerance and robustness for a single point or a single link failure. Routing protocol design is an important research area in wireless sensor networks.In WirelessHART network, every sensor node is a router and can delivery message for its neighbor. Routing and superframe schedule play very important role in WirelessHART for its reliability requirement and limited communication resources.In this work, we propose an approach for reliable routing graph construction and energy efficient link selection to enhance the robustness and prolong the network lifetime. In routing graph construction, we re-add a link for the nodes which has only one neighbor to transmit in the simplified graph. It can guarantee sufficient choice for link selection on the premise of the least possible hops. When selecting links, we mainly consider link quality, energy efficient and the number of hops to choose optimal links. We use the analytic hierarchy process to determine the weight coefficients. Redundant links and the link selection can increase the successful rate of the transmission and decline the number of retransmission for energy saving. And we design a superframe schedule according to this routing algorithm. Experimental results show that our proposed algorithm outperforms in terms of extending the network lifetime and reliability of message transmission.