## 4 Conclusions  
This study presents a significant advancement in underground mining communication systems by proposing a smart antenna system that integrates circular polarization and  
Figure 22: The general architecture of the proposed single-element square patch antenna with circular polarization and beam steering.  
beam steering. The four-element square patch array, paired with a Butler matrix for beamforming, demonstrates improved signal coverage, interference mitigation, and adaptability to the harsh underground environment. The system's performance, operating within the 5.52-5.99 GHz range with a 400 MHz bandwidth and gain of up to 9.69 dBi, highlights its potential for reliable communication through precise directional control. The integration of circular polarization resolves polarization mismatches, ensuring consistent signal transmission in multipath fading environments. Beam steering further enhances performance by directing signals efficiently, minimizing dead zones and interference, which is crucial for both safety and operational efficiency in mining operations. Future research could focus on several areas to further optimize and expand the functionality of the proposed system: (i) explore the use of advanced materials, such as graphene and metamaterials, to improve antenna performance; (ii) miniaturize antenna elements and integrate beam steering functionalities into more compact form factors, allowing for deployment in space-constrained environments such as underground mines; (iii) enhance frequency agility and bandwidth to support multi-frequency or wideband operation, making the system compatible with various wireless communication standards and services; (iv) integrate intelligent features like cognitive radio capabilities, machine learning algorithms, and adaptive signal processing techniques to improve the antenna system's adaptability in dynamic environments; (v) develop energy-efficient designs, including low-power phase-shifting components, power-aware beam steering algorithms, and energy harvesting technologies to extend the system's operational lifespan. The proposed smart antenna system, with its potential future enhancements, offers a robust, scalable solution for improving communication reliability and efficiency in underground mining and other challenging environments.  
Conceptualization, M.A.M., I.A., and H.I.; methodology, M.A.M., M.A.A., G.T.N., and I.A.; formal analysis, M.A.M., I.A., and M.A.A.; investigation, M.A.M. and M.A.A.; resources, I.A. and G.T.N.; writing--original draft preparation, M.A.M., M.A.A., and I.A.; writing--review and editing, M.A.M., M.A.A., I.A., H.I., G.T.N., J.Q., A.M., I.K., B.G., and B.M.; visualization, M.A.A., I.A., B.G., B.M., and I.K.; funding acquisition, M.A.M. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors would like to acknowledge the Sibanye-Stillwater Digital Mining laboratory (DigiMine) at the Wits Mining Institute (WMI), University of the Witwatersrand, Johannesburg, for providing the resources necessary to conduct this research.  
The authors declare no conflicts of interest.