Singly-Fed Rectangular Dielectric Resonator Antenna With a Wide Circular Polarization Bandwidth and Beamwidth for WiMAX/Satellite Applications

Novel wideband circularly polarized DRA with squint-free radiation characteristics

“…Zou et al 20 have introduced a RDRA excited by a spiral strip, achieving a CP bandwidth of 25.5%. In parallel, by exciting a RDRA through a unique conformal H-shaped metal strip, a wideband CP DRA with a CP bandwidth of 20% has been achieved 21 . Moreover, Yang et al 22 proposed a square DRA excited by a microstrip coupled cross-slot with four vertical metal plates around the DRA, achieving a CP bandwidth of 46.9% with an average gain of within the desired operating band.…”

Novel Wideband Circularly Polarized DRA With Squint-free Radiation Characteristics

“…In contrast, CP waves, which are usually excited by two orthogonal linearly polarized waves of equal amplitude and 90-degree phase difference, have received much attention because they offer more flexibility for the transmitter and receiver orientations along with the capability of mitigating polarization mismatch and suppressing multipath interference [6][7][8]. Recently, different shapes of the DR along with various feeding mechanisms have been introduced to achieve wideband DRAs, operating in CP, as a pathway to fulfill spectrum requirements by taking the advantages of better mobility and less multipath effects [9][10][11][12][13][14][15][16][17][18][19][20]. To design circularly polarized DRA, two orthogonal modes must be excited with a quadratic phase difference, which can be realized by single or multiple feed mechanisms.…”

“…On the other hand, having a multiple feed network provides a wider CP bandwidth but results in a large and complex feeding structure. In the literature, several designs of single-point feed DRAs have been introduced to enhance the CP bandwidth [12][13][14][15][16][17][18][19][20]. For instance, in [12], a wideband CP quadruple-strip-fed cylindrical DRA with a CP bandwidth of 25.9% using a pair of 90 • hybrid couplers has been presented.…”

“…Zou et al [15] have introduced a RDRA excited by a spiral strip, achieving a CP bandwidth of 25.5%. In parallel, by exciting a RDRA through a unique conformal H-shaped metal strip, a wideband CP DRA with a CP bandwidth of 20% has been achieved [16]. Moreover, Yang et al [17] proposed a square DRA excited by a microstrip coupled cross-slot with four vertical metal plates around the DRA, achieving a CP bandwidth of 46.9% with an average gain of 4.69 dBi within the desired operating band.…”

“…Furthermore, to widen the CP, the position of feeding structure with respect to the resonator plays an important role and can cause the deviation of the main beam from boresight. For example, the CP-DRAs in [14,16,18,[22][23][24] suffer from a large squint angle, which is more than 20°due to the asymmetry of the excitation and/or the resonator geometry. In this article, we have proposed a new technique to remove the beam squint effect and widen the CP bandwidth with radiation characteristic enhancement.…”