Parametric Analysis of Compact UWB-MIMO Antenna with Improved Isolation Using Parasitic Reflectors and Protruded Ground Strips

A Compact Multiple-Input Multiple-Output (MIMO) antenna of size 16 × 26 mm² (0.144 λ₀ × 0.234 λ₀) with improved isolation is presented in this paper. It covers the bandwidth of 2.7–14.9 GHz (FBW is 138.2%), which includes the entire UWB, X band, and K_u band applications. The elements in the structure are placed at a distance of 0.018 λ₀ (2 mm). Optimized values of two parallel strips are placed between the elements for isolation, giving│S₂₁│ > 15 dB in most of the band. For further enhancement, four small rectangular strips with different dimensions are protruded to the ground plane, resulting in improved isolation│S₂₁│ > 20 dB in most of the band. The radiation efficiency and peak gain values are 86–96% and 0.8–6.6 dBi respectively. Diversity performance is evaluated with the Envelope Correlation Coefficient (ECC < 0.06), Diversity Gain (DG > 9.975 dB) and Total Active Reflection Coefficient (TARC < − 10 dB). The Parametric study has been done for optimization values of the proposed model. The proposed model is simulated & fabricated on the FR4 substrate, tested and verified practically. The measured results almost follow the simulated results.