volume | PIER Journals

Abstract

An innovative four-port Coplanar Waveguide (CPW) Multi-Input Multi-Output Antenna (MIMOA) based on a Koch Curve Fractal (KCF) with high isolation is proposed in this article. The High Frequency Structure Simulator (HFSS) is used for performance analysis and parametric optimization. Initially, a KCF-based CPW-fed single-element patch antenna is designed, which is later transformed into a four-port MIMOA (FPMIMOA). The proposed MIMOA is fabricated on an FR4 substrate and offers a wide impedance bandwidth of 1.23 GHz (4.46-5.69 GHz), centered at 4.92 GHz. It exhibits excellent diversity performance, including a Channel Capacity Loss (CCL) of less than 0.4 bits/s/Hz, an Envelope Correlation Coefficient (ECC) below 0.004, a Diversity Gain (DG) greater than 9.8, a Mean Effective Gain (MEG) below 3 dB, and a Total Active Reflection Coefficient (TARC) less than -20 dB from port 1 to the other ports. It also demonstrates an isolation level of 28 dB across the operating band. Furthermore, the proposed MIMOA achieves a high radiation efficiency (η) of 94% and a gain of 3.14 dBi. The antenna has been fabricated and experimentally tested to validate the simulated results. This MIMOA is suitable for applications such as public safety, the 5G sub-6 GHz band (4.8-5.0 GHz), and the 5.2 GHz Wireless LAN (5.15-5.35 GHz).

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Dr. Ashwini Kumar

Dr. Basudha Dewan

Dr. Amit Kumar Jain

Dr. Pratish Rawat

Dr. Zahriladha Zakaria

Dr. Ahmed Jamal Abdullah Al-Gburi