A Novel Multiple Access Scheme with Physical Layer Security

Recently, owing to the rapid increase of wireless traffic, higher capacity and spectral efficiency wireless communication system have been developed. The non-orthogonal multiple access (NOMA) scheme has been studied as one of the potential solutions. In addition to the need of higher capacity and spectral efficiency, the demand for secure communication has grown. To satisfy these requirements, a novel chaos scrambling NOMA (CSMA) scheme is proposed in this paper. Each user's scrambling sequence is generated by specific chaotic equation. In the transmitter, each user's modulated symbols are scrambled by chaotic sequence and then sent on the same frequency spectrum. Simulation results indicate that CSMA is much superior to the current orthogonal frequency division multiple access (OFDMA) and two promising NOMA schemes, multi-user shared access (MUSA) and sparse code multiple access (SCMA).