Enhancing Energy Efficiency In Noma-Supported Cognitive Radio Networks For 5g

Abstract

This paper investigates energy efficiency (EE) performance of a non-orthogonal multiple access (NOMA)-based cognitive radio (CR) system for 5G communications. The proposed system incorporates Relays aided by unmanned aerial vehicles (UAVs), which operate through a phase of energy harvesting (EH) followed by numerous decode-and-forward (DF) communication stages. During the energy harvesting phase, UAV relays collect energy as of a dedicated power beacon (PB) to maintain sustainable operations. The secondary transmitter (ST) employs a harvested energy to communicate with the first UAV relay with the help of NOMA, while the primary transmitter (PT) transmits to the primary receiver (PR) under interference limitations. Following relays utilize the DF method to send the messages to their intended location.

We obtained the Signal-to-interference-plus-noise ratio (SINR) expressions, throughput alongwith energy efficiency across various system components. Simulations conducted in MATLAB assess how power allocation, interference constraints, and relay energy usage influence energy efficiency. The findings reveal that improving power allocation and interference management significantly boosts energy efficiency while maintaining reliable communication. This research offers guidance on creating NOMA-based CR systems that are both energy-efficient and spectrum-efficient for 5G and future networks.