MSE-based Precoding Design And Its Application In MIMO Collaborative Physical Layer Security

With the rapid development of wireless communication technologies in recent years,the quality of communication services and the speed of data transmission have been improved.The issue of security is an important issue in wireless communication theory.According to the characteristics of the wireless channel,the physical layer security improves the security performance of the system from the bottom of the information theory.However,as the complexity of the network increases,the traditional security layer-based physical layer security mechanism is difficult to provide an effective solution.This paper focuses on the multiple-input multiple-output(MIMO)downlink in cellular networks,and proposes a physical layer security mechanism based on Mean Square Error(MSE),which effectively utilizes the device to the device-to-device(D2D)and the impact of the relay node on the network ensure the physical layer security of the entire network while ensuring the quality of the respective transmission.When the traditional physical layer security precoding scheme calculates the security limit of the wireless system according to the security rate,the computational complexity is high,and it is difficult to implement the MIMO complex network with the cooperative node,and the security performance cannot be guaranteed.The mean square error is a common indicator in the estimation theory,and the computational complexity is low and the processing is convenient.This paper links the security theory with the estimation theory and proves that the security rate(the difference between the mutual information)and the MSE are critical.The security rate is equal to a special difference or a certain difference between the MSE of eavesdropping end and the MSE of target receiving end.The progressive progression is equal to the difference between the MSE.Based on the above theory,two MSE-based precoding schemes for optimizing physical layer security are proposed: virtual-signal-power precoding(VSP)scheme and low-signal-power precoding(LSP)scheme.It provides an effective reference scheme for the application of physical layer security theory to MIMO complex downlinks.In order to further improve the security of the physical layer,this paper introduces interference coordination and relay cooperation technology.While the D2 D user completes the information transmission,the eavesdropping party suffers interference stronger than the target receiving user,thereby effectively improving the security rate.The relay cooperation can also provide interference suppression for the eavesdropping user while enhancing the receiving of the target receiving user,thereby solving the problem that the eavesdropping of the user channel is better than the target receiving user channel.For the above complex MIMO downlink,the security layer-based physical layer security technology is difficult to implement,but the MSE-based VSP and LSP proposed in this paper can provide an effective solution.The specific mathematical proof and simulation analysis provide strong support for the above theory.This paper proposes the above-mentioned MSE physical layer security mechanism to effectively solve the physical layer security problem that cannot be solved by the traditional security rate.Provide new ideas for the development of physical layer security theory.