Research And Implementation Of Localization Algorithm In Wireless Sensor Networks

Wireless sensor network is the current international concerns, multidisciplinary high cross from the forefront of the emerging field of research focus. As early as in 1999, the United States magazine, "Business Week" said that "network of micro-sensor technology" is one of the most important technologie in the 21st century. Micro-electro-mechanical systems, wireless communications and digital electronic technology has given birth to the progress of wireless sensor networks(wsn).Its low power consumption, low cost, distributed and self-organizing feature information perception has brought a change.Through the deployment of large number of sensor nodes to the target region, WSN will change our world with the objective of the interactive. Detectability, including earthquakes, electromagnetic, temperature, humidity, noise, light intensity, the pressure, soil composition, moving objects to the size, speed and direction of the surrounding environment in a wide range of phenomena.Micro-sensor technology and wireless networking technology for wireless sensor networks provide a broad application prospects. From military applications, target tracking, environmental testing to space exploration, the future of WSN applications will be beyond our imagination. For most applications, unknown location-aware sensor data is meaningless. Sensor Node must be clear its position before details "in what position or region specific incident," and to realize the objectives of the external positioning and tracking.On the other hand, understanding of sensor nodes location information routing can also improve the efficiency of the network to provide namespace to the reported deployment of network coverage quality, and network load balancing, as well as the configuration of the network topology.GPS is the most widely location services, although for each sensor node can be equipped with GPS receivers, but will be cost, power, scalability, and issues such as the restrictions, or even in some occasions may simply not be achieved.The same reason, by the hundreds of sensor nodes of the network, it is impossible to deploy artificial each node. Therefore, we must adopt the mechanism and the position algorithm for solving the problem nodes.This paper around and range-free location algorithm launched a research and discussion, summed up the first location algorithm for wireless sensor networks in recent years of the status quo, and analyzed it.In this paper, both at home and abroad existing location algorithm on the basis of which addressed the anchor nodes sparse and the positioning of the mobile node, use of mobile anchor nodes continuously releases the location information to help unknown node positioning, effectively overcome the problem of sparse anchor nodes. On the basis of the DV-HOP algorithm,increase a method in the weighted forecast and recycling refinement.First of miscellaneous used to calculate preliminary estimate node positioning coordinates, and then using weighted least squares method trilateral measurements to calculate the new location,solved the uneven distribution network and mobile positioning results imprecise positioning of the nodes.Design of the wireless sensor networks positioning algorithm and automotive electronic map-matching algorithm, the positioning algorithm and automotive electronic maps combined.The main work and results included in this paper are as follows:1. In introducing the background and significance on the basis of summing up of wireless sensor networks positioning algorithm of the status quo. Analysis of different range-free algorithms, the results showed that: from a variety of performance indicators, free-range positioning algorithm is suitable for the requirements of sensor networks.But their problem is anchored by the high cost and lack of node high-density uniform distribution restrictions.Anchor mobile nodes and the weighted forecast cycle refinement of methods to better apply to mobile wireless sensor network node position.2. Details on wireless sensor networks positioning algorithm performance evaluation indicators, research DV-Hop position algorithm and the basic theory of Ranging.Including quality of miscellaneous, triangulation, trilateral basic measurement algorithm.Research shows that DV-HOP algorithm needs anchor nodes smaller proportion, computing and communications moderate volume, but by restricting the distribution of nodes in the intensive rules in the implementation of the network layout of the results is very good, but in sparse or irregular network, positioning communication to a radius of accuracy.3. Anchor node supporting mobile positioning, and joined the weighted forecast refinement and recycling methods, the first mobile anchor nodes using preliminary estimates of miscellaneous coordinates, and in the network continuously broadcasting their location information and then wait for positioning nodes according to Anchor node jump, which are estimated coordinates, and finally the use of weighted least squares method trilateral measurement cycle refinement to compute node location.4. Completion of the position algorithm combined with the electronic map in the Intelligent Transportation Systems Design and Implementation. Vehicle positioning algorithm and the integration of electronic map, the design of wireless sensor networks positioning algorithm and electronic map-matching algorithm.Track and vehicle positioning in the digital map information linked to the road network, which can be further guide path and path planning5. design of the improved algorithm simulation system, and with other positioning algorithm for the simulation results are compared.Position algorithm will be combined with electronic maps and GPS simulation results are compared,The results showed that more than similar algorithm precision positioning, smoother track position can be effectively used in vehicle navigation and other transport systems.In order to solve this sensor network range free-positioning algorithm anchor nodes and mobile nodes sparse asked Orientation. Anchor node supporting mobile positioning, and joined the weighted forecast and recycling refinement method. Simulation results show that the positioning performance, improved algorithm DV-HOP algorithm than the average error and error variance area decreased 10%~35% and 45%~50%. In the non-uniform distribution network, positioning results than DV-HOP more precise, effective solution is not the traditional location algorithm limitations. Through map-matching algorithm is position algorithm and automotive electronic map combining traditional GPS positioning function better, more accurate positioning, and more reliable.The study of the paper work in wireless sensor networks positioning algorithm as well as vehicle navigation and positioning, and other fields have a certain theoretical significance and value.