Research On Physical Layer Security Transmission And Authentication Protocol Based On Wireless Channel Characteristics

At present,wireless communication is increasingly integrated into all aspects of production and social life.A large number of important information related to the national economy and the people’s livelihood are transmitted through wireless channels.While it brings great convenience,it is more vulnerable to various illegal attacks due to the openness and broadcasting of wireless channels.Traditional security mechanisms are mostly based on cryptography and rely on algorithm strength to ensure data confidentiality and authentication reliability.There are problems such as high computational complexity,large time delay and difficult key management.They are not suitable for emerging communication scenarios with limited computing and storage capacity and delay sensitivity.In recent years,physical layer security based on wireless channel characteristics has been developing continuously.It uses the natural security attributes such as uniqueness,reciprocity and randomness of wireless channel to extract wireless channel characteristics for physical layer authentication and key generation.It has the advantages of low complexity,small delay and good compatibility,which provides a useful supplement to the high-level security mechanism relying on cryptography.Based on the classical physical layer security scheme,this thesis studies from the aspects of feature extraction,test statistics construction,quantization and process design,comprehensively analyzes the performance and influencing factors of various channel characteristics,distance measurement and quantization methods,and proposes a physical layer secure transmission and authentication scheme based on wireless channel characteristics,which integrates authentication and key generation process.The scheme simplifies the interaction process and improves the security performance.The main contributions and innovations are as follows:1.A transmission authentication scheme using Manhattan distance to construct test statistics is proposed.On the basis of analyzing and comparing the authentication performance of various distance measures and correlation measures,considering the discrimination and computational complexity,Manhattan distance is selected to measure the difference of channel characteristics of continuous frames,and theoretical modeling and simulation verification are carried out.Its discrimination is slightly better than the classical Euclidean distance,and the computational complexity is lower.2.A scheme design is proposed to dynamically adjust the number of authentication features and give consideration to authentication security and efficiency.The factors affecting authentication performance are comprehensively analyzed,including signal-to-noise ratio,terminal moving speed and the number of features used for authentication.It is found that increasing the number of authentication features can make up for the decline of authentication performance caused by terminal movement and environmental changes,and dynamically adjust the number of features used for authentication in different scenarios to maximize authentication performance and efficiency.3.A physical layer secure transmission and authentication scheme based on wireless channel characteristics is proposed.The fusion design of initial authentication and key generation,using the characteristics of channel and shared secret,realizes mutual authentication and key generation between communication parties through three interactions,and simplifies the interaction process.Using the idea of zero knowledge proof for reference,a one-way function is constructed by using difficult problems to realize authentication without divulging secret information,which improves the security.Using the reciprocity of wireless channel,the transmitter uses channel response to transform the interactive information,and the channel influence is naturally offset at the receiver,which can prevent eavesdropping and man in the middle attack.