Research On Security Transmission Based On Quantum Key Distribution In Millimeter Wave Massive MIMO Systems

With the development of communication technology,the fifth-generation mobile communication(5G)has become widespread.Compared with 2G which can make phone calls,3G which can get online and 4G which can meet the needs of mobile Internet users,5G has three characteristics: large capacity,high speed rate and low time delay.Because of these advantages,more and more devices can easily connect to the communication network.However,with the increase of the number of devices,a large number of devices are distributed in every corner of people’s life.How to ensure the information exchange between devices under the premise of security is a problem that must be solved.Millimeter wave massive multiple input multiple output(MIMO)technology is one of the key technologies of 5G,which can serve multiple users at the same time and greatly improve the system throughput.However,it will face many security threats and be vulnerable to attacks because of the high-speed data transmission,for example,wireless signal has the characteristics of opening and instability,the message transmitted in free space will be easily obtained by the eavesdropper’s device,and the lack of protocols to ensure that users receive the right information makes the system vulnerable to attack.The existing secure transmission scheme usually uses the classical encryption algorithm to ensure the communication security.Its security is based on the computational complexity of the algorithm,so it can’t detect the eavesdropping.Quantum key distribution(QKD)is based on the basic principle of quantum mechanics,which can make the two sides of communication generate and share a random key.Once a third party tries to eavesdrop,the two sides of communication will notice,so it has higher security.In order to make full use of the advantages of quantum key distribution in security and confidentiality and better ensure the safe transmission of information,this paper studies the secure transmission scheme combining quantum key distribution technology in millimeter wave massive MIMO system.The main contents of this paper are as follows:First,considering the two aspects of between base station and base station and between user and base station respectively,aiming at the problem that eavesdropping cannot be found on the transmission link between base stations,this paper proposes a secure transmission scheme that uses quantum key distribution to replace the classical encryption algorithm between base stations.Through the physical characteristics of quantum state,eavesdroppers on the transmission link can be found in time,so that switch to another secure link in case of eavesdropping.In addition,this paper also improves the classical secure transmission scheme from user to base station based on angel information of millimeter wave massive MIMO channel,which can not avoid the key error,so that it can also decrypt correctly in the case of partial error.Secondly,in order to solve the problem that the wireless communication link between the user and the base station is easier to be eavesdropped,this paper proposes a secure transmission scheme that uses quantum key distribution between the user and the base station.At the same time,it uses the method of wireless channel angle estimation to generate the reference sequence as the basis for quantum key distribution to select the quantum base.It not only uses the characteristics of quantum state to ensure the security of communication,the angle information of millimeter wave massive MIMO communication channel is also used to improve the key efficiency.