Statistical QoS provisioning for half/full-duplex cooperative non-orthogonal multiple access

Abstract

Power allocation plays an important role in cooperative non-orthogonal multiple access (NOMA) systems. To guarantee the quality of service (QoS) requirements of users, we present the cross layer power allocation algorithms for half-duplex cooperative NOMA (HD-CNOMA) and full-duplex cooperative NOMA (FD-CNOMA) systems respectively. From fairness standpoint, the optimization problem for each scheme aims at maximizing the minimum user effective capacity in a NOMA user pair under different delay QoS constraints. Due to the quasi-concavity of both problems, we propose a bisection-based cross layer power allocation algorithm for both cases to obtain the optimal solution. Numerical results show that proposed schemes significantly outperforms existing fixed cooperative NOMA schemes. Moreover, we also illustrate that proposed cooperative NOMA schemes are more suitable for low SNR environments compared to the optimized conventional NOMA scheme.