Research And Implementation Of Localization Algorithm In WSN

Wireless sensor networks (WSN) aroused extensive attention because of its low-power nodes, miniature, low-cost, self-networking and other features, are widely used in military, commercial, civil and so on. While, many messages which need to have the location information are valuable, so localization algorithm in WSN has become a hot spot, scholars have proposed a variety of localization algorithms, while each has insufficient, the main contradiction is between complexity and accuracy, for which this article mainly research the WSN node localization algorithm, to improve the positioning accuracy, under the condition of increasing the complexity to some extent.The main research contents and conclusions of this study are as follows:(1) Analyzing and summarizing current research, especially analyzing advantages and disadvantages of localization algorithm in some specific areas, and summarizing the common problems;(2) Analyzing the commonly used signal models in detail, and improving Shadowing model on account of the irregularities of radio signal;(3) Proposing a novel localization algorithm which is based on approach degree. In the algorithm, the use of PIT to estimate unknown node area, using the biggest-smallest approach degree to calculate the best virtual beacon nodes, and then by calculating the centroid to determine the unknown node position. This algorithm makes use of the virtual beacon node to a certain extent reduce the interference due to multi-path, diffraction signal strength and network costs, and combining unknown nodes and virtual nodes by the approach degree, to avoid overlapped error in some algorithm. The effectiveness of the algorithm is verified by simulation.(4) Designing and implementing a localization system-ADLS. This system will upload location information to the gateway through ad-hoc network, and the network topology, routing information and location information is displayed on PC. Through the analysis of ADLS, it can improve localization accuracy under the condition of increasing a certain complexity, and has good performance and is suitable for application in WSN.