Research On Wireless Sensor Network Localization Algorithm Based On Different Network Models

With the rapid development of Micro-Electro-Mechanical Systems, embeddedsystems, wireless communications and distributed information processingtechnology, the sensors have developed the capability of the perception, calculation,wireless network communication and the wireless sensor networks have arousedgreat concern. Localization technology which is one of the key techniques takesgreat significance in the effectiveness of wireless sensor networks. Only thepositions of all sensor nodes have been known, can the position of the event be clearand then the corresponding actions be taken. As many applications such asearthquake monitoring and target tracking, a number of sensor nodes need to bedeployed in the large intra-regional, and these features should be dependent on thenode positioning estimate automatically and precisely. Therefore, wireless sensornetwork positioning technology becomes a focus for researchers in recent years.In this paper, based on a large number of relevant literature and researches, thebackground and the significance of the wireless sensor network are introduced, andthe overall of the basics of wireless sensor networks are overviewed. In addition,some classical algorithms and system based on distance and range-free localizationin the wireless sensor networks are summarized.After analyzing the classical DV-Hop localization algorithm, this paper pointedout that the number of hops between nodes is too large and some part of nodesassembled can cause an analogue error in the original algorithm, which makes thepositioning accuracy of the unknown node not high. In order to reduce thepositioning error of the DV-Hop localization algorithm, a modified DV-Hopalgorithm called MDV-Hop positioning algorithm is proposed. MDV-Hop takesimprovements over DV-Hop from the following aspects: Firstly, the number of hopsbetween nodes is modified by setting the threshold; Secondly, the estimatecoordinates of beacon nodes and the deviations of actual position are used as acorrection factor to correct positioning results of unknown nodes; Finally, unknownnodes located outside the region due to the large error are modified. As the applications of wireless sensor networks are more and more extensive, the sensornode’s arrangement will be inevitably in the asymmetry distribution condition. Inorder to verify effectiveness of the MDV-Hop positioning algorithm, the positioningalgorithm has been applied in isotropic networks and C-type network model foranalysis and comparison.The MATLAB software has been used to verify the efficiency of the improvedalgorithms. Experimental results indicate that the classical DV-hop algorithm is notsuitable in the C-type network model; Compared to the classical DV-hop algorithm,the accuracy of the improved algorithm is higher and it is more evident in the C-typenetwork model.