Design And Implementation Of Physical Layer Security Transmission Algorithm In Multi-beam Satellite Communication System

Satellite communication With the rapid advancement of science and technology,multi-beam antenna technology has been widely developed and applied.However.the issue of information security in the development of satellite networks has become increasingly prominent.Therefore,the establishment of a multi-beam satellite network with a high security factor is crucial for the development of satellite communications.As computers continue to improve their computing power,traditional computation-based encryption methods will face enormous challenges.In addition,the distributed architecture and self-organizing nature of antenna networks make it difficult to implement key management and distribution.At present,the physical layer security technology has been widely used in the field of communications,especially in reliance on multi-antenna system channel diversity,randomness and reciprocity and beamforming,antenna selection,artificial noise assistance and other strategies to improve network security Significant achievements have been made in this area.While the system security has been significantly improved,it can also meet certain conditions such as bandwidth,power,design complexity,and overhead.Physical layer security is an information theory sense of security.It accomplishes cryptographic operations from the lowest level of the network protocol stack and can play a role in secure communications.Based on the application scenario of multi-beam satellite communication network,this paper studies the security encryption technology of the physical layer:Firstly,the demand analysis of the system network is carried out,and a physical layer security algorithm based on the three-dimensional Lorenz chaotic system to generate the key-to-signal amplitude-phase transformation and constellation scrambling is given.The algorithm makes full use of the chaotic sequence's initial value.Sensitivity,the chaotic encryption key is introduced to scramble the position of the constellation point,so that the transmission signal loses the characteristic information of the modulation mode,and the security risk caused by information leakage of the modulation mode is avoided,and higher security is achieved.The design and implementation flow of the algorithm is studied.The design and implementation flowchart of the algorithm is drawn,and the specific design and implementation of each module in the algorithm is performed.Then the physical layer security transmission algorithm is simulated and verified.The algorithm is evaluated from the aspects of sensitivity,effectiveness,reliability,and recognition of the modulation mode,and the effect of the algorithm on the performance of the communication system is discussed.And compares the bit error rate performance of the algorithm and the algorithm that generates the phase-to-phase transformation based on the one-dimensional Logistic chaotic system.The analysis results show that the proposed algorithm can effectively protect the information of the modulation mode and other information on the premise of ensuring the performance of the communication system.The security performance is very high and it has a great prospect in the field of communication.Finally,a communication system platform is set up to verify the algorithm,and the algorithm is downloaded to the board for testing,and the hardware resources consumed by the entire system are evaluated.Experimental results show the effectiveness of the algorithm,and the algorithm uses less hardware resources.