Abstract:
End spreading technology uses a sequence of multiple end information to represent the identity information, and each piece of end information was irrelevant to the information it conveys. Thus it can hide the real information of the user. However, the end spreading sequence has the problems of low resource utilization, poor autocorrelation and unable to realize secure communication among multiple users. The sparse code multiple access (SCMA) technology is introduced into the generation process of end spreading sequence, establish the system model of end spreading multi-user secure communication system based on SCMA, and elaborating on the codebook design allocation strategy and code-word loading and sending strategy designed in the model. After that, the prototype system is analyzed and experimentally verified from two aspects of security capability and quality of communication service. The experiment result shows that, end spreading multi-user secure communication system based on SCMA realizes the covert transmission of user information, and the receiver can correctly distinguish user information. With sparse coding, the system has a low error rate and good transmission performance under certain overload conditions.