Performance Analysis of Wireless Powered Cooperative NOMA-Based CDRT IoT Networks

This article investigates the outage performance of a wireless powered cooperative nonorthogonal multiple access-based coordinated direct and relay transmission (CDRT) Internet-of-Things (IoT) network with simultaneous wireless information and power transfer capable IoT master node. A method to remedy the high outage situation of a near user by exploiting information from earlier communication phase is proposed and analyzed. The competency of this method and the closed form of the outage probability for the users under practical variations, such as imperfect successive interference cancellation and different incentive transmission power levels for the IoT master node, are derived analytically and confirmed via simulation. In addition to that, our asymptotic analysis shows that it is not mandatory to enhance the outage performance of the near user in the final phase of CDRT by using many antennas in the high signal-to-noise-ratio regime. Moreover, a modified particle swarm optimization algorithm is introduced to solve a joint power splitting, time splitting, and power allocation for the proposed system. Numerical results from our analysis exemplify significant tradeoff between near user performance and the quality of service of the master node's client.