Compact Tightly-Coupled Self-Decoupled MIMO Antenna Using Internal Hybrid Tunning

This brief offers a compact, tightly-coupled, self-decoupled vias-based multiple-input multiple-output (MIMO) antenna pair with a common ground for a 5G system. The projected design comprises modified T-shaped tightly-coupled antenna elements. It is effortlessly helping to achieve sound decoupling across the desired band without using any extra decoupling circuit between the elements. It is revealed that the structure of the self-decoupled MIMO antenna tunes the inductive and capacitive (hybrid) effect of elements, which helps to achieve the decoupling of antenna elements. A relevant equivalent circuit model for coupled and decoupled MIMO antenna is proposed to validate the insight operation of this proposed theory. The hybrid tuning among the MIMO antenna elements reduces the coupling effect mutually by modifying the antenna shapes. The proposed self-decoupled MIMO antenna pair demonstrates low mutual coupling across the 5G NR frequency bands: n48 and long-term evolution (LTE) band 42/52 (3.2–3.6 GHz) with good diversity characteristics. Moreover, the one proposed design structure can offer dual-band self-decoupling features. The proposed structure provides 3.2-3.6GHz and 3.95-4.115GHz frequency bands. This structure can be optimize further to achieve dual-band/ wideband resonance in the design.