Frequency and bandwidth reconfigurable MIMO dielectric resonator antenna and its optimization using Taguchi neural network

Abstract In this article, a 1 × 2 bandwidth (BW) and frequency-reconfigurable dielectric resonator-based multiple input multiple output (MIMO) antenna array is presented for 5G sub-6 GHz (3.3–6.0 GHz)/Wi-Fi 6E (5.925–6.425 GHz)/Wi-Fi 5G (5.15–5.85 GHz) applications. Additional dual-ring-open loop resonator structures with varied dimensions are introduced within antenna’s feeding network to achieve BW and frequency reconfigurability. RF PIN and varactor diodes (VDs) are integrated with proposed structure to enable switching between various modes and continuous tuning of frequency and BW, respectively. Further, Taguchi neural network (TNN) has been incorporated to predict percentage bandwidth of proposed antenna, getting a maximum deviation of only 0.6% from actual value. The proposed structure operated from 4.98 to 6.5 GHz, achieving wide continuous frequency tuning of 20.36% in passband and 6.1% reconfiguration for notch band. It also demonstrates continuous BW tunability from 16.69% to 34.44% with measured BWs of 19.58%, 34.44%, and 16.69% at 0, 3, and 8 V reverse bias voltages of VDs, respectively. MIMO antenna array structure also shows enhanced gain performance with a peak gain of 11.03 dBi and an overall gain above 7 dBi in the whole operating band.