Location Algorithm Complex Area Of ​​wireless Sensor Network Node

Wireless Sensor Network technology, which has characteristics such as miniaturization, low power consumption, and self-organizing, can obtain the objective physical information and cognitive environment information, and can also be used for data storage, processing, forwarding, wireless communication and many other functions. As a result, WSN can be applied in a large-scale heritage protection, which can meet the requirements such as real-time monitoring of the site environment and timely warning. Self-localization technology of sensor nodes, which meet the demand of practical application, has become one of the supporting technology in WSN, and cause widely attention and research. According to whether it needs to accurately obtain the physical distance of nodes or not, the location technology is divided into two categories:range-based and range-free. For large-scale application scenario, range-free location algorithm such as DV-Hop is used, which is of low cost, simple thought, easy to implement and only based on network connectivity.Range-free localization algorithm, with only network connectivity information, to achieve high positioning accuracy, is based on a hypothesis, namely there is a mapping function between Euler distance and estimated distance for each pair of wireless sensor nodes. Estimated distance is obtained by the minimum hop count between nodes in a network and single path length, but for large-scale heritage, the monitoring area is complex. When wireless sensor networks are deployed in complex area, the mapping function no longer holds. As a result, using the DV-Hop algorithm under this scenario will bring a large localization error. In order to solve the nodes localization problem in complex areas which made wireless sensor networks anisotropic, this paper proposes a method based on region division, and then uses an improved algorithm for node localization. The main content is as follows:1. Research on complex area division algorithmFor the anisotropic wireless sensor networks in the complex area, first using the cyclotomic method define concave and convex nodes within the network, then find a dividing line based on the shortest path principle, and determines which area each node belongs to, finally realize node localization in the same division area. Through regional division, it can effectively avoid the complex region boundary’s bad effects on the shortest path between nodes and nodes localization accuracy.2. Improve the localization algorithm based on network connectivityDV-Hop is based on range-free localization algorithm, which achieves higher localization accuracy under uniform deployment of the network, but there is large error in random distribution network. The nodes are randomly deployed in the division area, through related analysis of the localization error, proposing improvement suggestion from three aspects: distance estimate between nodes, beacon node selection algorithm and position estimate optimization, to improve the node localization accuracy and algorithm adaptability.Finally, this paper carries on the simulation experiment. Results show that ACDT algorithm compared with the original algorithm, improves the localization accuracy, and reduce the bad effects of complex area on the node location accuracy.