Research On Key Technologies Of Sensor Configuration Optimization For IoT Applications

IoT (Internet of Things) has become a research hotspot in the world, which is designed to provide users with information exchange and intelligent control. As one of the supporting technologies of IoT, WSN (Wireless Sensor Network) is responsible for information sensing and transmission at the end of IoT. The whole net is consisted of large scale of sensor nodes with limited energy and communication capacity, which has important features such as energy confinement and high redundancy. In the current WSN, one net is built for one IoT application. However, IoT should be an information sharing platform with open mode, on which, all the IoT applications can use sensing information and intelligently control the WSN in an IoT system. So, how to achieve the optimal sensor configuration for IoT applications, in order to make WSN support more IoT applications longer, is a key issue to be resolved.To solve the sensor configuration optimization problem in WSN for IoT applications, this thesis studies the problem in two ways, sensor nodes selection and protection of the particular nodes. Firstly, to select the WSN sensor nodes, a wireless sensor node selection method is proposed, which based on GA to meet the needs of IoT application and the QoS architecture of WSN with considering of the optimal coverage. In detail, the method uses the maximum coverage of the area to be monitored and the least number of nodes as the optimization objective, and realizes the optimal set of wireless sensor nodes to monitor the area driven by energy efficiency consideration iteratively. Since the standard GA has defects such as slow convergence rate and easy fallen to local optimal solution, similarity judgment and adding new individuals are introduced. Secondly, with the optimization selection of wireless sensor nodes finished, by analyzing energy consumption of sensor nodes, characteristics of the special nodes which are easy to fail are obtained. Based on the characteristics, a method to identify the special nodes is studied. Then, by analyzing the influence on network coverage, named cover hole, which is caused by the special nodes failure, a safeguard mechanism based on greedy algorithm to avoid cover hole is proposed. Eventually, the method is tested via the simulation experiment and a case to verify the feasibility and efficiency in terms of the feasibility, efficiency and parameter settings respectively.