In this article, a novel wideband circularly polarized multiple inputs multiple output (MIMO) dielectric resonator antenna (DRA) has been proposed for WiMAX applications. The mutual coupling (MC) between closely placed DRA units at 0.5λ has been significantly reduced by using a new hybrid technique. The exclusive features of the proposed MIMO antenna include wide impedance matching bandwidth (BW), broadband circular polarization (CP) and suppressed MC between the radiating elements. The first step of hybrid technique is the employment of parasitic patch at an optimized distance beside the conformal metal strip of the two identical rectangular DRAs in order to generate CP wave along with a wide impedance matching BW over the same frequency range. In the final step, the mutual coupling is suppressed significantly along with the broadband circular polarization by placing the DRAs diagonally at an optimized position. The proposed MIMO antenna is the hybrid of the parasitic patch and the diagonal position of radiating elements. The CP BW offered by the proposed antenna is ~ 20.82% (3.58–4.40 GHz) in conjunction with an impedance-matching BW of ~ 38.51% (3.50–4.95 GHz). Moreover, MC less than -28 dB, is achieved over the entire band and -26 dB at 3.89 GHz (minimum of the AR) through the hybrid technique. The prototype of the proposed antenna geometry is fabricated and measured. A good agreement has been attained between the simulated and measured results.

A rectangular dielectric resonator antenna (DRA) with a broadband circular polarization (CP) radiation is presented using a single feed excitation. A simple feed method is proposed using an open half-loop antenna that consists of three metallic strips. Utilizing such an excitation has provided a circular polarization over a bandwidth of 7% that has been increased further to 13% by adding a concentric parasitic open half-loop in the structure. This has been achieved in conjunction with a 20% impedance matching bandwidth over the same frequency range. The configuration has been rigorously modeled using a method of moments (MoM) model. The computed and measured results are in good agreement.

A rectangular dielectric resonator antenna (DRA) that is excited using an outer-fed square spiral strip has been studied theoretically and experimentally. Utilizing such excitation has provided a circular polarization over a broad bandwidth of ~14% in conjunction with an impedance-matching bandwidth of ~11%. The structure has been rigorously modeled using a method of moments (MoM) model. A good agreement has been attained between computed and measured results.

A rectangular dielectric resonator antenna (DRA) has been excited using a unique conformal H-shaped metal strip. Using this excitation, the degenerate mode pair of first higher orderTE _δ13 ^x and TE ^1δ3 _y has been excited for bandwidth improvement and high gain. A broadband circular polarization (CP) over a bandwidth of ~20% (3.67-4.4 GHz) in conjunction with a wide impedance-matching bandwidth of ~27.7% (3.67-4.73 GHz) has been achieved. A CP beamwidth of 89° has been offered by the antenna in Φ = 0° plane and ~32° in Φ = 90° plane. A high gain of ~6.8 dBic has been provided by the antenna, which is a significant improvement to those circularly polarized rectangular DRAs reported in the literature for similar applications. This broad CP bandwidth and beamwidth can be considerably beneficial for the worldwide interoperability for microwave access (WiMAX) and satellite applications. Furthermore, the proposed antenna has been fabricated to validate the simulated results. The measured results have been observed to agree well with the simulated results.

In this article, a rectangular dielectric resonator antenna (RDRA) with circularly polarized (CP) response is presented for 5G NR (New Radio) Sub-6 GHz band applications. A uniquely shaped conformal metal feeding strip is proposed to excite the RDRA in higher-order mode for high gain utilization. By using the proposed feeding mechanism, the degenerate mode pair of the first higher-order, i.e., ${\mathrm{TE}}_{\mathsf{\delta }13}^{\mathrm{x}}$ at 4.13 GHz and ${\mathrm{TE}}_{1\mathsf{\delta }3}^{\mathrm{y}},$ at 4.52 GHz is excited to achieve a circularly polarized response. A circular polarization over a bandwidth of ~10%, in conjunction with a wide impedance matching over a bandwidth of ~17%, were attained by the antenna. The CP antenna proposed offers a useful gain of ~6.2 dBic. The achieved CP bandwidth of the RDRA is good enough to cover the targeted 5G NR bands around 4.4–4.8 GHz, such as n79. The proposed antenna configuration is modelled and optimized using computer simulation technology (CST). A prototype was built to confirm (validate) the performance estimated through simulation. A good agreement was observed between simulated and measured results.

A wideband circularly polarized rectangular dielectric resonator antenna (DRA) fed by single feeding mechanism has been studied theoretically and experimentally. The study has been carried out to find out the effect on different antenna parameters when a parasitic strip is attached to the wall beside the conformal metallic feed. The DRA is excited by an E-shaped metal strip. The novel feed produces a narrow impedance matching |S ₁₁ | <; -10 dB bandwidth of 7.94%. Further enhancement is carried out by introducing the parasitic patch at an optimal location on rectangular DRA, such configuration provided a measured circular polarization (CP) waves over a broad bandwidth of 22.01% (3.59 - 4.40 GHz) in conjunction with a wide impedance matching bandwidth of -23% (3.6 - 4.45 GHz). These results represent that; parasitic patch not only generate CP but also an increase by a factor of - 3 times in return loss as compared to those achieved by E-shape feed only. Simulation is done through computer simulation technology (CST-2017). The prototype of the proposed antenna geometry is fabricated and measured. Performance parameters demonstrate that the proposed antenna is well suitable for WiMAX applications. The simulated results agree reasonably with measurements.