Research On Physical Layer Security Of MIMO Two-Way Relay System

This paper studies the security of untrusted relay network in MIMO two-way relay cooperative communication system.In relay communication network,each node connected by relay has different sec urity level.In order to forward the information of all nodes,the relay node has the lowest security permission level.Therefore,although the relay in the communication network is used to transmit information,it may also be used as a eavesdropper to ste al information.In view of the above situation,this paper proposes the physical layer security model of the MIMO two-way relay cooperative communication network,designs the antenna grouping algorithm with low complexity,the second optimization of carrie r distribution optimization scheme and the proportional power distribution algorithm,which improves the total security capacity of the system.At the same time,theoretical analysis and simulation verify the usefulness of the proposed scheme.Firstly,according to the characteristics of MIMO two-way communication system,the physical layer security model of relay cooperative communication is built reasonably,and the security performance of the system is deduced theoretically.In this paper,the working mo de of cooperative relay is amplifying and forwarding,and the relationship between the security performance and amplifying coefficient of the system is also simulated.Secondly,for MIMO two-way relay communication system,this paper designs a low complexity antenna grouping scheme.The aim of this paper is to minimize the sum of channel correlation coefficients and optimize the antenna combination.Although the algorithm is suboptimal,it has low complexity and can improve the security performance of the system.In this paper,the improvement of the security capacity of the antenna grouping algorithm is analyzed theoretically,and the reliability and effectiveness of the algorithm are v erified by simulation.Then,the carrier resource allocation algorithm of MIMO two-way relay system is studied,and a second optimization algorithm is proposed.The second optimization carrier algorithm is a carrier assignment algorithm with very low complexity.This algorithm can obtain the optimal carrier assignment scheme.At the same time,because the algorithm divides the traversal process into two stages,it greatly reduces the complexity of the algorithm.At the same time,the stability and complexity of the algorithm are discussed and analyzed in detail.Finally,the energy resource allocation algorithm of MIMO two-way relay system is studied,and the proportional power allocation algorithm is proposed.The simulation results show that the proposed scheme has the best security performance.