Optimal user selection scheme in wireless powered downlink CNOMA communication under Nakagami-m fading channel

Abstract

Cooperative non-orthogonal multiple access (CNOMA) stands out as a promising approach for fostering widespread user connectivity and promoting fair allocation of network resources. For a self-sustainable, low complexity, high-speed, ultra-reliable data transmission we need user cooperative relaying with an optimal and low complexity user selection scheme. This research article models a Wireless power transfer (WPT) enabled user-assisted CNOMA communication network using Nakagami-m channel and compares the outage performance of user nodes at different existing relay selection techniques. A comparative outage performance analysis of several popular user selection systems is conducted through simulation in an effort to identify the best scheme with the least amount of complexity for the proposed communication network. However, in conventional cooperative communication networks optimal performance can never be achieved with low complexity schemes. It also provides a closed-form exact expression for outage probability and throughput at both the near and far user and the energy efficiency of the proposed communication system using the optimal scheme. The expressions derived are validated through Monte Carlo simulation. The outage performance analysis is obtained at the optimal scheme varying different parameters. The performance of the WPT-assisted CNOMA is compared with that of a Simultaneous Wireless Information and Power Transfer (SWIPT) assisted CNOMA using various existing user selection schemes to find the best combination of techniques.