# Energy-efficient framework based on optimal antenna selection in S-NOMA supported UAV IoT networks

## TL;DR

This paper proposes an energy-efficient framework for UAV-assisted IoT networks using optimal antenna selection and S-NOMA to improve data rates and energy efficiency.

## Contribution

The novel contribution is an energy-efficient framework with optimal antenna selection in S-NOMA for UAV IoT networks.

## Key findings

- S-NOMA achieves a data rate of 15.2 bps/Hz at 30 dB SNR, outperforming conventional NOMA.
- Energy efficiency improves by 14.4% with optimal antenna selection over random selection.
- The framework considers transmit, circuit, and UAV hovering power for energy efficiency analysis.

## Abstract

Owing to the high emissions and increased energy consumption of the expanding heterogeneous internet-of-things (IoT) devices across terrestial and non-terrestial networks, achieving the energy sustainability in future IoT networks is the main challenge. This paper presents an energy efficient framework utilising spatial non orthogonal multiple access (S-NOMA) technique in UAV assisted IoT networks. An antenna selection algorithm is proposed that selects a set of active antennas enabling user fairness. The numerical formulations for the air-to-ground communication links in the S-NOMA system is also obtained. Further, the paper proposes a power consumption model for the S-NOMA enabled network to carry out the energy efficiency analysis. The transmit power consumption, circuit power consumption and UAV hovering power is taken into account. The proposed S-NOMA framework with optimal antenna selection is evaluated against conventional NOMA and random schemes. Simulation results demonstrate that S-NOMA achieves superior performance in terms of data rate and energy efficiency. It is observed that at an SNR of 30 dB, the proposed method with achieves a data rate of 15.2 bps/Hz, outperforming conventional NOMA which achieves 6.4 bps/Hz. Also, the energy efficiency improves by 14.4% at transmit power P=25 dBm with the proposed antenna selection scheme over random selection scheme. This improvement is attributed to the enhanced spatial gain and power-aware antenna selection, thus resulting in sustainable UAV IoT networks.