In this paper, we study the resource allocation algorithm design for multiple-input single-output (MISO) multicarrier non-orthogonal multiple access (MC-NOMA) systems, in which a full-duplex base station serves multiple half-duplex uplink and downlink users on the same subcarrier simultaneously. The resource allocation is optimized for maximization of the weighted system throughput while the information leakage is constrained and artificial noise is injected to guarantee secure communication in the presence of multiple potential eavesdroppers. To this end, we formulate a robust non-convex optimization problem taking into account the imperfect channel state information of the eavesdropping channels and the qualityof-service requirements of the legitimate users. Despite the nonconvexity of the optimization problem, we solve it optimally by applying monotonic optimization which yields the optimal beamforming, artificial noise design, subcarrier allocation, and power allocation policy. The optimal resource allocation policy serves as a performance benchmark since the corresponding monotonic optimization-based algorithm entails a high computational complexity. Hence, we also develop a low-complexity suboptimal resource allocation algorithm which converges to a locally optimal solution. Our simulation results reveal that the performance of the suboptimal algorithm closely approaches that of the optimal algorithm. Besides, the proposed optimal MISO NOMA system can not only ensure downlink and uplink communication security simultaneously but also provides a significant system secrecy rate improvement compared with the traditional MISO orthogonal multiple access systems and two other baseline schemes. Index Terms-Non-orthogonal multiple access (NOMA), multicarrier systems, full-duplex radio, physical layer security, imperfect channel state information, non-convex and combinatorial optimization.
Tackling the channel uncertainty in the PLS was studied in REF , showing that FD-NOMA is able to secure both DL and UL transmissions simultaneously and obtain a significant system secrecy rate improvement compared with the traditional FD scheme.
Robust and Secure Resource Allocation for Full-Duplex MISO Multicarrier NOMA Systems
IEEE Transactions on Communications
IEEE Transactions on Communications
Mathematics Computer Science