Abstract
This paper presents compact two-port antenna arrays with linear and circular polarization based on a miniaturized patch radiator with extremely low cross-polarization radiation. The primary radiator employs a conventional rectangular patch loaded with multiple slots and meander-line structures to increase the equivalent capacitance, thereby lowering the resonant frequency without enlarging the antenna footprint. Owing to the inherently low cross-polarization radiation of the miniaturized radiator, two compact 2-port array configurations are implemented: the first provides polarization diversity under linear polarization, while the second employs a hybrid coupler to achieve dual circular polarization. Both arrays operate at 4.3 GHz and possess compact physical dimensions with stable radiation performance. Compared with state-of-the-art works, the proposed designs exhibit a significantly reduced size while maintaining competitive radiation characteristics, making them suitable for space-constrained wireless systems.
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Funding
Co-funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.
Besides that, this publication has emanated from research jointly funded by Taighde Éireann – Research Ireland under Grant number \(13/RC/2094\_2\), the European Union’s Marie Sklodowska-Curie Actions under grant number 101126578 and was supported in part by University of Galway.
In addition, the authors extend the appreciation to the Deanship of Postgraduate Studies and Scientific Research at Majmaah University for funding this research work through the project number (R-2026-125).
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Conceptualization: A.T.-T., T.L.-T., and M.A.; Methodology: T.H.-T. and Y.M.Q.; Software: A.T.-T., T.H.-T., and T.S.; Validation: M.A., Y.M.Q., and P.L.; Formal analysis: T.L.-T. and T.S.; Investigation: A.T.-T. and T.H.-T.; Resources: M.A. and P.L.; Data Curation: T.S. and T.L.-T.; Writing - Original Draft: A.T.-T. and T.H.-T.; Writing - Review & Editing: M.A., Y.M.Q., T.S., and P.L.; Visualization: A.T.-T.; Supervision: M.A., Y.M.Q., and P.L.; Funding Acquisition: M.A., Y.M.Q., and P.L. All authors have read and agreed to the published version of the manuscript.
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Tran-Tuan, A., Hoang-Thu, T., Le-Tuan, T. et al. Compact 2-port linearly and circularly polarized antennas using low cross-polarization miniaturized patch. Sci Rep (2026). https://doi.org/10.1038/s41598-026-46704-6
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DOI: https://doi.org/10.1038/s41598-026-46704-6
