10.57647/mjee.2026.2002.10

Hexagonal Microstrip MIMO Antenna with Defected Ground Structures for ISM/IoT Application

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  • Farzaneh Talebi1,
  • Pejman Rezaei*1,
  • Sina Kiani1,
  1. Electrical and Computer Engineering Faculty, Semnan University, Semnan, Iran

Received: 2024-11-06

Revised: 2025-02-18

Accepted: 2025-05-15

Published Online: 2026-04-21

Copyright (c) 2026 Farzaneh Talebi, Pejman Rezaei, Sina Kiani (Author)

Creative Commons License

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

How to Cite

Talebi, F., Rezaei, P., & Kiani, S. Hexagonal Microstrip MIMO Antenna with Defected Ground Structures for ISM/IoT Application. Majlesi Journal of Electrical Engineering. https://doi.org/10.57647/mjee.2026.2002.10
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Abstract

In this manuscript, an original multiple-input multiple-output (MIMO) array antenna is proposed. The proposed array consists of two mirror-image elements placed adjacently. The proposed MIMO antenna is designed on the Rogers 4003C substrate with dimensions of 54 × 26 × 0.508 mm3. The recommended MIMO antenna exhibits a fractional impedance bandwidth of 13.79% (5.4-6.2 GHz), and achieves an element isolation greater than 22 dB. The proposed MIMO array demonstrates a gain of 5 dB with an efficiency of 95% at 5.8 GHz. Additionally, the MIMO array has a channel capacity loss less of than 0.2 b/s/Hz, an envelope correlation coefficient of ≤ 0.02, a diversity gains of ≥ 9.96 dB, and a mean effective gain ratio between elements of 1 dB. Due to its optimal operating frequency, high efficiency, and compact size, this antenna is an appropriate candidate for ISM/IoT applications.

Keywords

  • Decoupling network,
  • Defected ground structure,
  • ISM/IoT applications,
  • Microstrip MIMO antenna,
  • Mutual coupling
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