Research Of Joint Authentication Technology Based On Carrier Frequency Offset And RSS

In wireless communication network, due to the broadcast characteristic of wireless channel, the security of communication is always facing serious challenges. The traditional wireless security technologies,which often rely on public key mechanism and encryption algorithm, may not only be easily cracked by powerful attackers, but also increase the burden of computing resource in wireless network. The security mechanism using characteristic parameters of physical layer in wireless communication can improve the level of security, and reduce resource consumption and time delay.Physical layer security authentication technology utilizes the characteristic parameters of the physical layer in wireless channel, extracts the specific parameters of the wireless network and uses some authentication strategies to authenticate the source of data packets. Based on this technology, we apply classical Neyman-Pearson method of hypothesis test theory and propose a joint authentication method using carrier frequency offset (CFO) and received signal strength (RSS) in this thesis. Using RSS in authentication can effectively take advantage of the characteristics of wireless channel, but is vulnerable to spoofing attack.While hardware-related CFO, is not easy to be imitated but cannot the recognize locations of nodes. Both these physical layer parameters are easily obtained, and are complementary for each other. We monitor and analyze CFO and RSS at the same time to enhance the security of wireless communication systems. The main works of this thesis are listed as follows.(1) The thesis proposes a joint authentication method using CFO and RSS, to identify the source when receiving data packet in communication.The authentication threshold, which can maximize detection probability,can be deduced through false alarm probability, and then be used in the comparison with the sample mean value of the deviation sample matrix to accomplish hypothesis tests. At last, we combines the results of the tests by strict strategy, in which we claim it legal only when both results are legal, in order to develop superior authentication detector.(2) The thesis designs a MATLAB simulation and sets experimental environment to simulate the communication process. The simulation data of two physical layer parameters obtained from the parameter model are analyzed. The receiver operating characteristic curve is used to evaluate the performance of the scheme. By comparing with the two single parameter schemes, it can be verified that the performance of the proposed scheme is improved. Meanwhile, the impact factors of the scheme performance are analyzed in order to compare the performance under different SNR and different sampling sizes.(3) The thesis designs and implements experiments to verify the proposed scheme. This thesis sets up an experimental platform by utilizing software defined radio (SDR) based on GNU Radio and USRP. We design the process and control groups for the experiments, and make practical tests to get sample values of physical layer parameters. The sample values are collected and analyzed by MATLAB. The experimental results show that the method has better performance in actual communication environment.