The Study On Localization Technology Of Wireless Sensor Networks

As a key technology with rapid development in civil and military application field, the research of wireless sensor network is of great significance to the nation and society. Wireless sensor network is consisted of vast low-cost, tiny wireless sensor nodes with random distribution in the form of self-organization. The perception and processing between nodes should bind with the location information of node in wireless sensor network. Therefore, localization technology is part of the supportive technology of sensor network. However, due to the open wireless environment of the wireless sensor network and the restriction of application environment, most of the nodes are free of being monitored. Therefore, the safety of node in the process of locating is also a crucial issue to the positional technologies which need to be solved.This paper aims at researching the mechanism of localization in wireless sensor network node and that of secure localization.Firstly, it is based on wireless sensor network, and introduces the basic principles of node location estimation, then briefly describes the method of trilateral survey. It mainly focuses on the problem that exits in DV-Hop algorithm, and uses the characteristic of RSSI ranging to optimize the algorithm in the aspects of total network communication's cost and positional accuracy.Secondly, this paper aims at the internal attack mode of malicious beacon node's location deception, and analyzes the security threat to DV-Hop localization algorithm caused by distributing the false information of malicious beacon, on the basis of which a secure optimal algorithm for malicious beacon node defending is putted forward. Simulation results show that, the secure localization algorithm can effectively improve the ratio of the locating node, and reduce the influence of positional accuracy of DV-Hop algorithm caused by malicious attack.Finally, this paper explains the principle of wormhole attack, and establishes the external wormhole attack model of hidden channels between beacon nodes, then analyzes the influence of DV-Hop localization algorithm caused by this model. Whereafter, it puts forward a kind of beacon verification mechanism to bear the wormhole attack. By virtually increasing the average correction value in a way of defending the hidden channel wormhole attacks between the defensive beacons, the ability of bearing attack of localization algorithm is improved.