Optimal Power Allocation in Hybrid NOMA-PLNC Network with Ambient Backscattering

In this paper, a sum capacity maximization of the downlink non orthogonal multiple access (NOMA) based wireless network is studied in the presence of ambient backscattering (ABS). By incorporating a downlink NOMA with ABS, the mobile user can also be utilized as a Internet of Things (IoT) devices. Further, this paper employs the well known physical layer network coding (PLNC) scheme to support a pair of nodes in a single time slot. To ensure the quality of services (QoS) of each user, optimal power is allocated at the downlink level with total transmit power and minimum data rate requirement per user constraints using Lagrangian’s function. In addition, end-to-end outage probability of the proposed NOMA-PLNC based wireless network with ABS is derived. It is noted that the outage performance of the proposed wireless network with ABS is significantly improved. Moreover, considerable improvement in the far user capacity is achieved using ABS. Simulation results are presented to validate the analytical expressions.