High-permittivity Dielectric Resonator Antenna Research Articles

Investigations on Photoresist-Based Artificial Dielectrics With Tall-Embedded Metal Grids and Their Resonator Antenna Application

Novel photoresist-based artificial bulk dielectrics with tall-embedded metal grids are investigated and their radiation characteristics are studied in detail. The embedded metal grid substantially increases (around six times) the effective permittivity of the low permittivity base photoresist material, and enables excitation with a simple direct microstrip feed to radiate effectively at frequencies similar to a high-permittivity dielectric resonator antenna (DRA). Moreover, the grid changes the near fields inside the resonator and introduces novel modes that are completely different than those of usual DRAs. A set of artificial resonator antennas is designed, lithographically fabricated, and measured to demonstrate the new modes resonating at 17 and 19 GHz with 2% and 6% bandwidth and 7.6 and 6.6 dB broadside gain, respectively, with suitable cross-polarization levels of better than $- {20}\;\text{dB}$ . These new modes do not appear simultaneously, and can be excited separately by varying the length of the microstrip feed.

A Low-Profile and High-Permittivity Dielectric Resonator Antenna With Enhanced Bandwidth

A dielectric resonator antenna of very high permittivity has been proposed. The antenna is designed based on a multilayered structure. To realize low profile and relatively large impedance bandwidth simultaneously, two separate dielectric resonators of high permittivity are placed symmetrically on top of the antenna structure. A low-permittivity dielectric substrate is inserted between the resonators and the ground. The total height of the antenna is 1.57 mm or 0.039λ (λ is the wavelength at the center frequency.) An enhanced bandwidth of 10.49% has been realized. The proposed antenna has stable radiation patterns across the whole operating band. Relatively high antenna gains over 6 dBi and a low cross-polarization level of -25 dB are also achieved.

Harmonization of a Bandpass Shielding Enclosure and Its Internal Antenna

This paper investigates the way to harmonize a bandpass shielding enclosure (BPSE) and its internal antenna for achieving better performance. The harmonization greatly depends on the relative position of the antenna with respective to the adjacent periodic elements and the sideboards of the BPSE. For this harmonization, an internal high-permittivity dielectric resonator antenna is suggested due to its compact size and the minimum distance allowed between the antenna and the metallic sideboards of the BPSE. In addition, an appropriate zone for locating the antenna is suggested in terms of the relative position between the antenna and its adjacent BPSE elements. According to these suggestions, the antenna can be placed deep within a BPSE corner, a position which is often required in practice.

Design and Analysis of a Novel Compact High Permittivity Dielectric Resonator Antenna

A very compact and efficient dielectric resonator antenna is proposed and investigated. The novel structure is analyzed using two numerical methods and design guidelines are established. Moreover, it is shown that-by using very high permittivity materials and appropriate design of the resonator and its feeding structure-wide frequency coverage is possible even at cellular frequencies. Simulation results are reported showing the effectiveness of the proposed antenna structure.

Numerical investigation on compact multimode dielectric resonator antennas of very high permittivity

Two well known numerical techniques, the Finite Element Method (FEM) and the Finite Integration in Time Domain (FIT), have been applied to study a low volume high permittivity dielectric resonator antenna. The paper demonstrates that the design of a compact size and wide frequency coverage dielectric resonator antenna (DRA) for ISM band is possible by proper selection of the resonator shape in combination with appropriate resonant modes. Numerical results for one particular antenna design are reported.

T-strip-fed high-permittivity rectangular dielectric resonator antenna for broadband applications

A rectangular low-density, high-permittivity dielectric resonator antenna (DRA) excited by T-shaped microstrip feed offering a 2:1 VSWR bandwidth of ∼22% at 2.975 GHz is reported. The design methodology and experimental results of the antenna are discussed. The excellent gain and radiation performance of the proposed antenna projects it as a potential candidate for telecommunication applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 226–228, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21131

On the Wideband High-permittivity Dielectric Resonator Antenna with Parasitic Patches

Three mirctostrip-fed high-permittivity cylindrical dielectric resonator antennas (DRAs) with parasitic patches for wideband applications are proposed. For each case, a wide impedance bandwidth of ˜10% is achieved by exciting the fundamental TM110 mode of the cylindrical DRA and the parasitic-patch modes. The return loss, radiation pattern and antenna gain of these configurations are studied experimentally.

Low-profile high-permittivity dielectric resonator antenna excited by a disk-loaded coaxial aperture

A low-profile equilateral-triangular dielectric resonator antenna (DRA) of very high permittivity is excited by a disk-loaded coaxial aperture. The loading disk is placed centrally on the aperture of a 50 /spl Omega/ subminiature version A (SMA) connector for impedance matching. The measured return loss, radiation patterns, and antenna gain of the proposed configuration are presented.

High‐permittivity dielectric resonator antenna excited by a rectangular waveguide

AbstractA low‐profile equilateral‐triangular dielectric resonator antenna (DRA) of very high permittivity (εr = 82) is excited with the use of a rectangular waveguide. It is found that the present configuration has a very wide impedance bandwidth of 11.4%, which is 3.8 times of that of the previous aperture‐coupled DRA. The return loss, radiation patterns, and antenna gain of the new configuration are investigated. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 157–158, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10401