Abstract
In this paper, a microstrip patch antenna is designed and proposed in a 2 × 2 MIMO configuration for use in 6G wireless communications in upper mid-band like 7.125–8.4 GHz. The design of the antenna is imposed on a dual fractal geometry strategy to improve performance parameters. The first aspect of the geometry uses a circular fractal structure of up to four iterations, and the second aspect uses a circular slot to adjust the radiating patch. The application of fractal geometry aids in enhancing circuit properties, and a partial ground plane is utilized to improve bandwidth and provide stable gain over the operating frequency range. The antenna has a wideband response of 5.25 to 11.3 GHz, and it is appropriate for future 6G systems. The gain of the antenna is between 2 dB and 3.6 dB over the band. Performance analysis entails S-parameters, radiation patterns, and important MIMO parameters like Envelope Correlation Coefficient (ECC), Channel Capacity Loss (CCL), Total Active Reflection Coefficient (TARC), and Mean Effective Gain (MEG) that are all within acceptable levels. An equivalent circuit model of the antenna is also created to aid the design. Despite slight mismatches between calculated and measured values due to excessive soldering during processing, the overall performance is still acceptable and can be optimized with accurate fabrication processing. The proposed design is also useful for the following 5G NR band: n47 band (5.855–5.925 GHz), n96 band (5.925–7.125 GHz), n102 band (5925–6425 GHz), and n104 band (6425–7125 GHz).
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Data availability
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
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Ashwini Kumar– Conceived the antenna design concept, performed simulations, and optimized the fractal geometry parameters.Rajeev Kumar– Assisted in design methodology development, conducted literature review, and contributed to simulation analysis.Bright Keswani – Contributed to data interpretation, manuscript drafting, and critical technical revisions.Amit Kumar Jain – Oversaw fabrication process, performed experimental measurements, and validated simulation results.Pratish Rawat– Assisted in measurement setup, processed experimental data, and prepared performance analysis plots.Basudha Dewan– Coordinated the project, integrated results, and finalized the manuscript for submission.
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Kumar, A., Kumar, R., Keswani, B. et al. Design of MIMO antenna for 6G applications supported by fractal geometry. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38312-1
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DOI: https://doi.org/10.1038/s41598-026-38312-1
