10.57647/jtap.2026.2005.02

Design and Experimental Validation of a High-Efficiency FR-4 Microstrip Patch Antenna Based on a Single Air-Gap Configuration for Wireless Applications

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  • Sarah Kareem Mohammed1,
  • Muayyed Jabar Zoory*1,
  1. Department of Physics, College of Science, Mustansiriyah University, Baghdad, Iraq

Received: 2026-04-01

Revised: 2026-04-18

Accepted: 2026-04-23

Published in Issue 2026-10-31

Published Online: 2026-06-10

Copyright (c) 2026 Sarah Kareem Mohammed, Muayyed Jabar Zoory (Author)

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

1.
Mohammed SK, Zoory MJ. Design and Experimental Validation of a High-Efficiency FR-4 Microstrip Patch Antenna Based on a Single Air-Gap Configuration for Wireless Applications. J Theor Appl phys. 2026 Oct. 31;20(5). Available from: https://oiccpress.com/jtap/article/view/18864
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Abstract

In this work, a low-cost FR-4 microstrip patch antenna with a single air-gap layer is proposed to achieve enhanced efficiency and gain while keeping structural simplicity and fabrication capability, which was experimentally performed as well. Unlike multilayer designs or metasurfaces, which may achieve better radiation efficiency or gain through additional orders of complexity in the design and fabrication processes, the introduced approach leverages a simple structural modification to make significant improvements while ensuring fabrication simplicity. The effect of the air-gap thickness on the performance of various antenna types is systematically studied using full-wave simulations, followed by experiments for validation. These results show an increase in realized gain from 2.29 dB to greater than 7.68 dB, and radiation efficiency exceeded 75%. Moreover, the air gap allows a change in resonant behaviour and helps to increase bandwidth. In this study, the results of both are compared and show good agreement. This simple and low-cost method improves the effectiveness of FR-4-type antennas in wireless transmission scenarios, especially for devices operating below 6 GHz.

Keywords

  • Microstrip patch antenna,
  • Single air-gap antenna,
  • FR-4 substrate,
  • Gain enhancement,
  • Radiation efficiency,
  • Wireless communication systems
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