NOMA and massive MIMO assisted physical layer security using artificial noise precoding

In this paper, combined secrecy performance of two 5G technologies viz. massive multiple-input-multiple-output (massive MIMO) and non-orthogonal multiple access (NOMA) for a wireless communication network is investigated. Both, large scale path loss and small scale Rayleigh fading channel are taken into account. An amplify-and-forward (AF) relay is considered in the presence of an eavesdropper, both having multiple antennas. The achievable secrecy rate is obtained for the given system model using the suitable linear precoding method, the artificial noise precoding, and the secrecy performance is compared with the existing systems. Results show that the proposed approach outperforms existing systems for a particular range of signal-to-noise ratio (SNR). To improve the performance for all SNR values, artificial noise (AN) precoding is used. The frequently used linear precoding methods are also compared to get the suitable technique. Simulations are carried out for the verification of results.