# A Dual-Band Flexible MIMO Array Antenna for Sub-6 GHz 5G Communications  
[PERSON]  
1 Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (D.M.J. ); [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
1 Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
2 Department of Mechatronics, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
3 Department of Information and Communication Technology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
4 [PERSON]  
6 Centre for Communications Technology, London Metropolitan University, London N7 8 DB, UK; [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
1 Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (D.M.J. ); [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
1 Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (D.M.J. ); [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) [PERSON]  
1 Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; [EMAIL_ADDRESS] (D.M.J. ); [EMAIL_ADDRESS] (R.M.D. ); [EMAIL_ADDRESS] (K.N. ); [EMAIL_ADDRESS] (S.P.G.) Footnote 1: email: john.d.m.d.m; jv.m. parameters such as sufficient gain and a broader bandwidth must be maintained while achieving compactness, which is a challenging task given the increasing demand for miniaturized devices [2]. Despite this, achieving an extremely compact size for Sub-6 GHz antennas is constrained by the large operating wavelength (\(\lambda\)). Miniaturizing the aperture area can degrade the gain and efficiency, thereby impairing radiation performance. Although mm-wave bands offer potential, their implementation faces challenges such as limited coverage, severe fading, and high costs. Consequently, researchers have focused on developing compact multiband antennas for Sub-6 GHz with optimized performance characteristics [3; 4]. Numerous methodologies have been explored to boost the performance of Sub-6 GHz antennas. For example, ref. [5] introduced a compact tri-band wearable antenna using an artificial magnetic conductor reflector, achieving reduced SAR and improved gain, albeit with a high volume. In [6], a multiband four-port antenna was designed with a unique lozenge-shaped DGS to improve isolation. While it achieved a low profile and enhanced isolation, its peak gain across all bands remained at just 4 dBi. Similarly, a slotted cavity-based antenna in [7] provided vertical polarization and omnidirectional characteristics, but its non-planar shape and limited bandwidth were drawbacks. In [8], a dual-band antenna utilized a meta-inspired network to enhance isolation and MIMO performance, but the design suffered from large size and low gain. A transparent antenna using metallic mesh, proposed in [9], offered decent bandwidth but had poor efficiency and fluctuating gain. In [10], a metasurface-based Sub-6 GHz antenna demonstrated a wider bandwidth and improved gain, but its isolation was limited to 15 dB and the design suffered from increased volume. Collectively, these studies highlight the difficulty of achieving wider bandwidth, higher gain, enhanced isolation, and compactness simultaneously in Sub-6 GHz antennas.