Research On Key Generation Technology Based On Wireless Channel State Characteristics

The natural openness of the wireless channel makes various applications implemented by it vulnerable to security threats.Although traditional encryption mechanisms can provide security for wireless application scenarios,they cannot adapt to various new wireless networks more efficiently,especially networks with high mobility and limited resources.The key generation mechanism based on the characteristics of the wireless channel utilizes the inherent time-varying,reciprocity and spatial decorrelation characteristics of the wireless channel itself,which can be easily applied to various types of wireless networks,thereby providing efficient and lightweight protection for them.For the key generation mechanism based on wireless channels,this thesis mainly completes the following tasks:Aiming at the information coordination phase of the key generation mechanism,this thesis proposes an optimization scheme based on LDPC codes.Although it is theoretically proved that LDPC codes can reach the Shannon limit indefinitely,in many practical applications,the design of LDPC codes will be limited.Because convolutional codes have memory properties,convolutional LDPC is also memorable,which solves the problem of limited code length.Therefore,this thesis optimizes the conventional LDPC code by introducing convolutional codes and then optimizes the information coordination process realized by it.Through experimental analysis,the proposed scheme can effectively optimize the information coordination process,thereby improving the usability of the entire key generation mechanism.This thesis proposes an efficient key generation scheme based on channel state information.Compared with many current schemes that use the characteristics of received signal strength,channel impulse response or phase to achieve key generation,the key generation mechanism based on channel state information proposed in this thesis has a higher key generation rate.At the same time,in order to ensure the efficiency of the key generation process,the proposed scheme will pre-process the original data before the quantization stage and perform data smoothing,thereby reducing the bit error rate between the receiving and sending bit sequences after the quantization coding.By obtaining experimental data from real scenarios for analysis,this solution can generate shared keys for wireless nodes more efficiently to ensure the security of the communication process.