A 2 × 2 Sequentially Rotated Polarization Reconfigurable Dielectric Resonator Antenna Utilizing Switchable Feed Circuit for Sub‐6 GHz Applications

In this communication, a 2 × 2 polarization reconfigurable (PR) sequentially rotated (SR) dielectric resonator antenna (DRA) array is presented to resonate within the IEEE 802.11a band. The array is formed of a novel resonator composed of a rectangular dielectric resonator (RDR) excited by a copper strip of hooked T‐shaped monopole to excite two degenerate resonant modes and confirming the circular polarization (CP) radiation. The proposed resonating element is optimized to operate at 5.8 GHz with the RDR dimensions being 10 × 5 × 10 mm 3 . A 2 × 2 array which is formed of the proposed resonator with a feeding circuit constitutes a single Wilkinson power divider (WPD), a single out‐of‐phase Schiffman coupler, and couple quartile branch line couplers (BLC). The polarization reconfigurability is obtained using positive–intrinsic–negative (PIN) diodes located at the BLC inputs as current switches. With proper PIN diodes switching, the radiated fields can be set to either right‐hand circular polarization (RHCP) or left‐hand circular polarization (LHCP). To investigate the initiated array resonance performance, an equivalent impedance circuit of the postulated array is proposed based on the array sub‐components’ equivalent lumped elements before simulation and measurements. The 100 × 40 mm 2 array possessed an impedance bandwidth of 12.07% for RHCP and 12.03% for LHCP within the IEEE 802.11a band. The maximum realized gain was 8.31 dBi with axial ratio (AR) bandwidth of 12.04%. The obtained results verified that the suggested array can emit two CP conditions with reasonable accord between the simulated and measured ones.