A Novel Approach to Secure RSMA Networks

Abstract: This letter introduces a novel data-dependent interleaving technique designed to enhance the security of rate-splitting multiple access (RSMA) networks by protecting the common stream from eavesdropping threats. Specifically, we exploit the RSMA structure by interleaving the common bits of each user based on a sequence derived from their private bits. By decoding its private stream, the legitimate receiver reconstructs the interleaving sequence set by the transmitter and successfully de-interleaves the common stream. Therefore, the common part is successfully prevented from being intercepted by an eavesdropper who is unable to deduce the dynamic changing interleaving permutations. To ensure dynamic interleaving sequences, a private bit selection approach that balances the trade-off between security and system efficiency is proposed. Simulation findings confirm the effectiveness of the suggested method, showing notable security improvements while maintaining robust overall system reliability.