Optimization Study Of Wireless Sensor Network In Monitoring High Speed Railway Infrastructure

The infrastructure is one of six core systems of high-speed railway, so, it is of important significance to monitor the service condition of high speed railway infrastructure. So far, our country monitors the service condition of high speed railway infrastructure with trackwalker and track inspection car. And the monitoring data is transmitted in wire style. Such monitoring system can’t get accurate data. It’s cost is expensive and it isn’t conducive to maintaining. The wireless sensor network based on Zigbee technology is used to monitor the high speed railway infrastructure service in this paper. And the wireless sensor network used to monitor high-speed railway infrastructure is set. This network has the characteristics such as low power consumption, low cost, no wiring and easy maintenance.The network is divided into sensor node layer, access layer and convergence layer from bottom to top. Considering the cost and complexity of the network, this paper optimizes the constitution of sensor nodes in the sensor node layer firstly. The initial population, fitness function and genetic operator of genetic algorithm are designed to find the optimal solution rapidly and accurately. Then this paper optimizes the constitution of nodes in access layer. The constituted optimization model of AP node based on the maximum bandwidth utilization is established. And the constituted optimization model of ZED node under the cover of AP node based on the maximum bandwidth utilization is established. In order to increase the expansibility of the network, the constituted optimization model of access layer nodes is also established when common sensor node or sensor node with weights is added into the existing network. This paper uses particle swarm optimization (PSO) algorithm to solve the model in the three situations, and designs the flow of finding the optimal constitution of access layer nodes based on the PSO algorithm.The energy consumption of node is mainly used in sending data, so the pros and cons of data transmission path decide the lifetime of network. The communication network of wireless sensor network in monitoring high-speed railway infrastructure is divided into the upper tree backbone and the lower star monitoring network. The communication address and frame of the nodes in this network is designed to reduce the communication cost and energy consumption. And the minimum spanning tree algorithm which uses communication power cost between nodes as weight is used to achieve topology optimization of the communication network. So, life of the whole network is extended. This paper simulates the constituted optimization of sensor node layer nodes, the constituted optimization of access layer nodes and the topology optimization of communication network. The result shows that the optimized network is a high speed railway infrastructure monitoring network with low cost, low power, real time and effective.