Security And Optimization Localization In Wireless Nenworks

With the gradual increase of wireless network applications, related wireless network technologies are getting more and more attentions. Among them, Wireless sensor networks (WSNs) is one of the emerging technologies which have attracted much attention in recent years. No-matter in the military application field or others, such as environmental protection, traffic management and health-care field, WSNs have a wide application prospects. As an key supporting of WSNs technology and research’s hot spot, node positioning has great significance both on the basic theory method and application basic research of wireless sensor networks. Node secure localization has become a key issue. At the same time, with the rapid development of wireless communication technologies, the indoor positioning technologies get more and more attention. Radio frequency identification technology (RFID) with non-contact, non line-of-sight, low cost and high precision, becomes the optimization technology in the field of indoor location. Because of the complexity of the indoor environment, multipath effects and interference phenomenon are relatively serious, improving the RFID indoor positioning accuracy and robustness of the algorithm is extremely important.Based on security and optimization idea, researches are done to improve localization precision and security of the wireless network.Firstly, a novel localization algorithm based on reputation mechanism is proposed to improve the robustness of the node positioning system in wireless sensor networks. This algorithm increases the malicious beacon nodes detection rates, and reduces the positioning error. The algorithm is efficient in self-positioning of sensor nodes in distributed wireless sensor networks, and the localization accuracy and safety are greatly improved.Secondly, after analyzing the drawbacks of the two classic indoor location algorithms:LANDMARC and VIRE, an improved algorithm is proposed on combining of the nonlinear interpolation algorithm. The location precision of improved algorithm is significantly higher than VIRE algorithm.Finally, a novel RFID localization algorithm based on fuzzy clustering and fingerprint updating is proposed to improve the accuracy of the location system in indoor environment.