Wideband Circularly Polarized Dielectric Resonator Antenna With a Square Spiral Microstrip Feedline

Abstract

Abstract-A rectangular dielectric resonator antenna (DRA) with a square spiral microstrip feedline is investigated in this paper. The design utilizes a feeding structure to excite two resonant modes (T E δ11 and T E 1δ1 modes) of the rectangular DRA that are spatially orthogonal in polarization and in phase. The antenna with the proposed feeding structure has provided a measured circular polarization (CP) over a bandwidth of ∼ 15.5% in conjunction with an impedance-matching bandwidth of ∼ 31.25% at the same frequency range. The gain of the dielectric resonator antenna varies between 6.8 and 7.2 dBi across the bandwidth (7.5 ∼ 8.75 GHz). Reasonable agreement between the simulated and measured results is obtained.

A state-of-art review on performance improvement of dielectric resonator antennas

“…For case of single point feed, the shape of the resonator plays the crucial role to generate spatially orthogonal modes, while in multipoint feed, this can be generated by the feeding network and independent of the shape of the dielectric resonator . In case of DRA, the research on only circular polarization and circular polarization with other charateristics are quite remarkable.…”

“…A combination of coaxial probe and helix type conducting tape was used carefully for realization of the idea, which became more directive than that of those convectional antennas. A square spiral shaped microstrip line was use for feeding purpose of a rectangular DRA of ɛ r = 9.6 by Zhang et al to realize the circular polarization over a 3 dB axial ratio bandwidth of 15.5% by exciting TE δ11 and TE 1δ1 modes.…”

The Analysis of a Wideband Strip-Helical Antenna with 1.1 Turns

“…In this design, it compromises to achieve the minimum numbers. Table 1 shows the comparison between the proposed strip-helical antenna and other designs of helical antenna in [6,7,[9][10][11]. Although the proposed antenna has an axial height of half a wavelength, its overlapped bandwidth is about 2 times that proposed in [7].…”

“…Recently, some helical/spiral excited circularly polarized dielectric resonator antennas (DRAs) with compact size have been proposed in [9][10][11]. For example, the helical excited DRA in [10] has an AR bandwidth of ∼13%, and the square spiral excited DRA in [11] has an AR bandwidth of ∼16%.…”

A Simple Broadband Flat-Gain Circularly Polarized Aperture Antenna With Multiple Radiation Modes

“…By using broadband CP antennas, not only the multipath effects can be mitigated, but also the complexity inherent in the multiservice wireless systems can be reduced. In recent years, many broadband CP antennas have been proposed [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Among them, wide apertures with single feed structure have been widely studied, owing to their features such as wide impedance bandwidth, low cost low profile, and easy fabrication.…”