A Coverage Model Of Wireless Sensor Network Nodes Deployment Under Emergency Rescue Circumstance

At present, it pays more and more attentions for human life and humanistic care in society. When a disaster occurs, the requirement of emergency rescue capabilities should be increased. In recent years, as a emerging practical technology, wireless sensor network can enhance disaster prevention and rescue capabilities. And the wireless sensor nodes deployment is the key of the coverage reliability, particularly in the emergency condition. So it becomes a urgent practical problem to solve.The five main content are as follows:(1) From the point of view of probability, it defines the nodes deployment coverage reliability of wireless sensor network for the target in a certain confidence level of the confidence area. And it establishes the coverage model of Wireless sensor network node deployment in emergency condition, namely, the mathematical formula of the node number, the confidence level, perception radius and the critical valve of coverage rate.(2) When it comes to the network coverage area, it puts forward a new calculation algorithm to solve the problem in a specific area which composes of circulars intersection area.This algorithm can compute exactly the area of multiple curved polygon formed by the intersection of the same calculation circle, and the process is relatively simple and small calculation of amount.In general, a ordinary computer can quickly get the calculation results of the large area. It is a kind of algorithm with application value.(3) According to the new algorithm put forward by the paper, it uses VB programming language developing the simulation system of the nodes deployment of wireless sensor network, providing a simulation platform for the next experiment spilled randomly wireless sensor nodes.(4) Start up the wireless sensor nodes deployment simulation system, and set up the network parameters and have a large number of simulation experiments. According to a large number of simulation data analysis, It turn out to be at least the number of nodes to meet area coverage rate in certain confidence level.(5) At the last, according to the parameter fitting, it gets a coverage model of wireless sensor network nodes deploymentunder emergency rescue circumstance. And the model provides the basis for reliability parameter design. At the same time, in some certain confidence level, it meets a specific area of coverage in the minimum requiring number of sensor nodes. And it provides a reference basis that the quantity of wireless sensor nodes at least should be spilled which can meet the requirements of the area coverage rate of wireless sensor network.