A Co-Planar Waveguide-Fed MIMO Antenna for Dual-Band Wireless Applications

This paper presents a simplified Multiple-Input Multiple-Output (MIMO) antenna tailored for dual-band applications, featuring a co-planar waveguide (CPW) fed configuration that integrates ultra-wideband (UWB) and narrowband capabilities. The single element design employs a circular patch with a central rectangular bar and circular slot, achieving impedance bandwidths from 3.96-9.89 GHz and 12.09-18.16 GHz, with a peak gain of 3.83 dBi. In MIMO configuration, a parasitic element effectively reduces mutual coupling, achieving mutual coupling less than -20 dB, while orthogonal element placement enhances the polarization diversity, crucial for the multipath environments. The antenna's compact size (18.5 mm × 46.8 mm) facilitates integration into various platforms, delivering a peak gain of 4.77 dBi at 7.65 GHz, low envelope correlation coefficients (ECC < 0.001), and high diversity gain (approximately 10 dB). Comparative analysis highlights the design's competitive advantages in bandwidth, isolation, gain, and efficiency, addressing miniaturization and coupling challenges, and making it a robust solution for next-generation wireless systems.