Research On Secure Data Transmission Technology In Sparse Antenna Array

In the next generation mobile communication system,high-speed data transmission is requirement of users,and the security is another requirement which has transformed to a key issue.From the security point of view,this thesis first proposes a physical layer secure transmission method based on sparse array to achieve secure communications.These sparse arrays are optimized with two objective functions in genetic algorithm.It uses iteratively the genetic algorithm to produce multiple sparse array structures with low side lobes,and then creates a codebook.Both theoretical analysis and simulation results show that the proposed method can ensure the communication security.Second,because the uniform linear array cannot guarantee the safety of the vertical direction,so the antenna subset selection scheme by the one-dimensional linear array is extended to planar antenna array.Then array antenna subset selection method and antenna sub-line selection method are proposed respectively.Through comparison,antenna subset selection can improve safety performance of system better so as to avoid information leaks.Finally,on the basis of the hybrid antenna array,hybrid beam forming technology was studied.Discussed how to optimizes digital and analog parts in the separated hybrid beamforming system so as to provide security services the information transmission in antenna array.