Journal of Applied Science and Engineering

Published by Tamkang University Press

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Design of self-diplexing antenna using meandered open loop resonators

 2026

 Volume 32

S Imaculate Rosaline1, Namitha K S1, and Alphones Arokiaswami2

1Department of ECE, Ramaiah Institute of Technology, Bengaluru

2NTU, Singapore

Received: September 2, 2025
Accepted: April 4, 2026
Publication Date: May 17, 2026

上傳圖片

Geometric layout of the proposed Antenna

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

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This work introduces a compact microstrip self-diplexing antenna tailored for dual-band application at 1.5 GHz and 2 GHz employing meandered open-loop resonators (MOLRs). The design incorporates two MOLRs linked through a centrally positioned T-junction acting as a power divider, enabling effective separation of frequency channels within a reduced footprint. The antenna is fabricated on a FR-4 substrate characterized by a dielectric constant of 4.4, a loss tangent of 0.02, and a thickness of 1.6mm. The complete layout occupies a 50 x 50 mm² area, making it well-suited for use in compact RF front-end modules where space is limited. Each resonator is dimensioned to achieve its respective resonance frequency while maintaining undesired coupling effects. According to the simulated S-parameters, the return loss remains better than-15 dB, and the isolation between
the two channels exceeds-40 dB. The fabricated prototype showed strong agreement with the simulation data upon measurement. To ensure human safety, a Specific Absorption Rate (SAR) performance analysis was also performed using a human phantom model for the associated antenna. Owing to its compact nature and effective performance metrics, the proposed diplexer is a promising candidate for L-band wireless systems, including GPS, telemetry, and Internet of Things (IoT) applications.

Keywords: Self-diplexing Antenna; Meandered open loop Resonator; Isolation; Specific Absorption Rate; Defected ground plane.

  1. [1] S. A. Ali, M. Wajid, M. S. Alam, and M. D. Nair, (2025) “A compact SIW dual-functional design with integrated filter and self-diplexing antenna” International Journal of Electronics 112(8): 1560–1577. DOI: https://doi.org/10.1080/00207217.2024.2393346.
  2. [2] R. K. Barik and S. Koziel, (2024) “Ultra-miniaturized HMSIW cavity-backed reconfigurable antenna diplexer employing dielectric fluids with wide frequency tuning range” Scientific Reports 14(1): 27767. DOI: https://doi.org/10.1038/s41598-024-79609-3.
  3. [3] A. Rezaei, S. I. Yahya, and L. Nouri, (2023) “Design and analysis of a compact microstrip lowpass–bandpass diplexer with good performance for wireless applications” International Journal of Microwave and Wireless Technologies 15(7): 1099–1107. DOI: https://doi.org/10.1017/S1759078722001465.
  4. [4] H. C. Jayatilaka, D. M. Klymyshyn, M. Börner, and J. Mohr, (2011) “Compact thick metal diplexer with multi-coupled folded half wavelength resonators” Progress In Electromagnetics Research C 18: 1–8. DOI: doi:10.2528/PIERC10100410.
  5. [5] Y.-X. Ji and J. Xu, (2014) “Compact BPF and diplexer using capacitively loaded  λ/4  shorted meander line resonator” Journal of Electromagnetic Waves and Applications 28(1): 112–118. DOI: https://doi.org/10.1080/09205071.2013.857617.
  6. [6] S. K. Bavandpour, S. Roshani, A. Pirasteh, S. Roshani, and H. Seyedi, (2021) “A compact lowpass–dual band-pass diplexer with high output ports isolation” AEU-International Journal of Electronics and Communications 135: 153748. DOI: https://doi.org/10.1016/j.aeue.2021.153748.
  7. [7] S. Kumar, S. Kumar, and C. S. Prasad. “A Co-linearly Polarized Highly Isolated Full Duplex Antenna Using Novel DGS”. In: 2024 Second International Conference on Microwave, Antenna and Communication (MAC). IEEE. 2024, 1–5. DOI: 10.1109 / MAC61551 . 2024 .10837522.
  8. [8] A. A. Khan and M. K. Mandal, (2019) “Compact self-diplexing antenna using dual-mode SIW square cavity” IEEE Antennas and Wireless Propagation Letters 18(2): 343–347. DOI: 10.1109/LAWP.2018.2890790.
  9. [9] A. Iqbal, M. Al-Hasan, I. B. Mabrouk, and T. A. Denidni, (2023) “Simultaneous transmit and receive self-duplexing antenna for head implants” IEEE Transactions on Antennas and Propagation 71(11): 8592–8601. DOI: 10.1109/TAP.2023.3312920.
  10. [10] M. R. Salehi, S. Keyvan, E. Abiri, and L. Noori, (2016) “Compact microstrip diplexer using new design of triangular open loop resonator for 4G wireless communication systems” AEU-International Journal of Electronics and Communications 70(7): 961–969. DOI: https://doi.org/10.1016/j.aeue.2016.04.015.
  11. [11] D. Zhang, S. Xia, A. Ren, and Q. Wu, (2024) “A diplexer antenna with extremely high isolation for co-site duplex applications” AEU-International Journal of Electronics and Communications 182: 155344. DOI: https://doi.org/10.1016/j.aeue.2024.155344.
  12. [12] P. PourMohammadi, H. Naseri, N. Melouki, F. Ahmed, Q. Zheng, A. Iqbal, G. A. Vandenbosch, and T. A. Denidni, (2024) “Highly-isolated compact self-diplexing antenna” AEU-International Journal of Electronics and Communications 173: 155025. DOI: https://doi.org/10.1016/j.aeue.2023.155025.
  13. [13] Y. Xu, S. Gong, and Y. Guan, (2012) “Coaxially fed microstrip antenna for harmonic suppression” Electronics letters 48(15): 895–896. DOI: https://doi.org/10.1049/el.2012.1070.
  14. [14] A. Chinig, A. Errkik, L. E. Abdellaoui, A. Tajmouati, J. Zbitou, and M. Latrach, (2016) “Design of a microstrip diplexer and triplexer using open loop resonators” Journal of Microwaves, Optoelectronics and Electromagnetic Applications 15(2): 65–80. DOI: https://doi.org/10.1590/2179-10742016v15i2602.
  15. [15] Y. S. Mezaal, S. K. Khaleel, B. M. Alameri, K. Al-Majdi, and A. A. Al-Hilali, (2024) “Miniaturized microstrip dual-channel diplexer based on modified meander line resonators for wireless and computer communication technologies” Technologies 12(5): 57. DOI: https://doi.org/10.3390/technologies12050057.
  16. [16] D. Chaturvedi and A. Kumar, (2023) “A QMSIW cavity-backed self-diplexing antenna with tunable resonant frequency using CSRR slot” IEEE Antennas and Wireless Propagation Letters 23(1): 259–263. DOI: 10.1109/LAWP.2023.3323008.
  17. [17] R. H. Elabd, A. H. Hussein, and A. J. Al-Gburi, (2025) “High-isolation microstrip two-port diplexer and full-duplex antenna with metamaterial-based filters” Discover Applied Sciences 7(10): 1044. DOI: https://doi.org/10.1007/s42452-025-07409-z.
  18. [18] M. Shaheen, N. Mahmoud, M. Ali, M. Nasr, and A. Hussein, (2022) “Implementation of a highly selective microstrip diplexer with low insertion loss using square open-loop resonators and a T-junction combiner” Radioengineering 31(3): 357–361. DOI: 10.13164/re.2022.0357.