Research On Secure Capacity Optimization And Access Control Based On Beamforming And Artificial Scrambling

With the development and popularization of the mobile communication technology, the security of the wireless communication network has become a hot issue in information security. In the traditional system, the security of information is guaranteed by cryptography. However, with the improvement of computing performance, the traditional encryption algorithm cannot guarantee the security of information. To make the transmission security rely on not merely the encryption key is becoming an urgent problem in the field of information security. And using the physical characteristics of wireless communication to improve security of wireless communication systems is a better solution. We focuses on the physical characteristics of using the wireless communication systems to improve its security, the results are obtained as follows:(1) To solve the problem that the amount of information received by the normal node is reduced after the source node is influenced by the artificial noise, we propose the method to maximize the security capacity for the main channel. This algorithm is used to perform artificial jamming on a wireless communication network in which there is an eavesdropper. Simulation results show that the proposed algorithm can achieve the maximum security capacity.(2) By investigating the capacity of the main channel in multi-relay systems, we introduce the method to optimize security capacity based on beamforming and cooperative jamming. Under the constraint of given total power, a joint design scheme of cooperative beamforming and artificial noise is proposed, with which the security capacity of the multiple input single output system can be improved. Simulation results show that the hybrid method proposed in this paper provides more security capacity than the single use of beamforming or single use of cooperative interference.(3) Considering the scenario that the state channel information (CSI) is unknown, a non-blind beamforming algorithm is introduced, and the system security capacity is analyzed. An access control algorithm based on artificial noise and beam forming is proposed. Through stochastic method, the system security throughput is derived. Simulation results show that the security capacity of the non-blind beamforming system is larger than that of the blind beam forming system.