| With the rapid development of wireless communication technology and the increasing prosperity of mobile applications which is driven by powerful wireless devices,varieties on network services have been significantly improved.Thus,the security of wireless communication network is becoming more and more important.Compared with the traditional infrastructure based mobile communication,the infrastructure free wireless self-organization network may encounter more serious security problems.The insecurity factors are not only from external malicious attacks but also from the capture of nodes inside the network.In multitudinous network attacks,the attack based on user identity is common,so the efficient user identity authentication mechanism is particularly important.In recent years,more and more people begin to pay attention to solve the authentication problem utilizing the wireless resources to compensate the traditional authentication mechanism drawbacks.In this thesis,the physical layer security in wireless self-organization networks is studied.Based on the characteristics of wireless fading channel,such as mutual convenience,spatial uniqueness,fast time variability and unpredictability,an excitation-response authentication algorithm for physical layer is proposed.In order to reduce the risk of exposure of the authentication information in the air interface,the proposed algorithm firstly utilized the unit-directional property of hash function,which encrypted the shared key and randomized the key.At the same time,it also proposes a physical layer authentication mechanism to protect the authentication information and prevents the authentication information transmitted by the air interface from being illegally stolen.Secondly,we use the detection method based on the maximum likelihood ratio and the constellation mapping function that suppresses noise amplification to improve the authentication efficiency.In addition,the authentication information is introduced into the binary hypothesis verification,and the identity authentication of the user is determined according to the correlation between the statistical parameters and the detection threshold.Finally,the key feature is used to initialize the user authentication binary hypothesis,which improves the accuracy of user authentication detection. |
