Industrial Wireless Networks WIA-PA Multi-path Routing Protocol Research

With the development of information technology, the industrial field devices are becoming digitization, networked and intelligent, while the central nervous of the control system posed by these intelligent devices is control network. At present, the control network is developing in direction to industrial Wireless network, and which is becoming the hot view of the field of automated industrial control, and have got some Preliminary results, such as Wireless HART, SP100, etc the foreign wireless networks at home and abroad. With an independent intellectual property right, WIA-PA, an industrial wireless networking standard has also been launched in China for process automation. Industrial wireless networks will become a trend of industry in the future.With self-organization, self-healing Smart Mesh network routing mechanisms, WIA-PA (Wireless Networks for Industrial Automation-Process Automation) is a kind of special industrial wireless networks, which could adapt to the dynamic changes in the network and ensure network reliability and instantaneity. With the support of "863 national key project", this technique is completed by more than 10 domestic institutions, including Chinese Academy of Sciences, Southwest University, Chongqing University of Posts and Telecommunications, etc. Through the application of industrial wireless network, to a certain extent, could reduce costs and avoid the complexity and perils of wire routing and provide a safe, reliable and convenient way for harsh industrial environments to monitor industrial processes. Hereon, the industrial wireless WIA-PA can not only be applied to industrial automated control system, but also building automation, environment, health and safety monitoring, asset management and energy management fields. Industrial wireless network WIA-PA nodes equipments are powered by batteries, which has a limited power supply. However, it is still an important question for WIA-PA researchers to reduce the consumption of network communication and improve network reliability and instantaneity, and prolong the working hours of the network. It is also quite significant for the widespread use of industrial wireless network WIA-PA.For the mesh network communication, the overall performance of the network depends on the routing technology. At present, WIA-PA routing algorithm is not mature enough, and the existing mature wireless network algorithms are self-organizing wireless networks such as DSDV, AODV, DSR, and so on. Through participating in WIA-PA study, in allusion to the characteristics and requirements of WIA-PA network, considering the characteristics of the existing wireless routing algorithm, and based on multipath, source routing, on-demand routing idea, the author of this paper has proposed a multi-path routing protocol for industrial wireless network WIA-PA.In this paper, the author first briefly analyzes the background and research significance of the development of industrial wireless network, and generally describes the structure, key technologies, technical field of industrial wireless network, etc. Then introduces and makes a comparative analysis of several typical single-path routing protocol and multi-path technology shortcomings and advantages. At the same time, several typical extension algorithms of multi-path of DSR are analyzed. Finally, based on the idea of multi-path, source routing and the on-demand routing in advance and the analysis of the problems of applying MSR protocol to WIA-PA network, the author considers the reliability, instantaneity, and energy consumption of WIA-PA network communication, to which the DSR routing policy has been improved to accommodate, in order to make the WIA-PA network communication more reliable and real-time, and to a certain extent, reduce the energy consumption so as to prolong the survival time of the entire network. This paper focuses on improving route discovery and routing update mechanism. In the route discovery process, a separate path selection function has been built with accordance of node residual energy and the end to end delay; in the route maintenance process, according to the conditions of node energy level, RTT value and the number of backup path remaining, etc., the author carries out the on-demand routing in advance to ensure the reliability and efficiency of the route. In the last place, on the NS2 simulation platform, the author compares the WMA_DSR (WIA-PA Multi-path routing-dsr), MSR and DSR protocols on the properties of routing reliability, data packet delivery ratio, end to end average delay, network lifetime, etc.Simulation results show that good effects could be achieved by the proposed routing protocol algorithm WMR_DSR in improving network reliability, instantaneity, and consuming reduction, etc. This routing protocol algorithm could also be well applied to WIA-PA network, and finally the survival time of the entire network has been effectively extended. In the static network environment, WMR_DSR routing algorithm could prolong the survival time of the WIA-PA network as long as approximately 5%.