High-gain Dielectric Resonator Antenna Research Articles

A wideband high-gain dielectric resonator antenna based on mullite microwave dielectric ceramics

In this paper, the high-quality factor mullite microwave dielectric ceramic is employed to introduce in dielectric resonator antenna (DRA). The microwave dielectric properties of ɛr ∼ 5.8, Q × f ∼ 31 240 at 9.66 GHz, and loss tangent tanδ = 1/Q ∼ 2.7 × 10−4 can be obtained by the solid-state reaction method in mullite microwave dielectric ceramic sintered at 1700 °C. On this basis, the resonant modes of the proposed broadband high-gain rectangular DRA are analyzed by using a dielectric waveguide theoretical model and the antenna performance is evaluated by a commercial CST Microwave Studio 2021® software. It has been found that the proposed rectangular DRA can provide a broad bandwidth of 35.9%, a maximum gain of 10 dBi at 3.61 GHz, and a radiation efficiency of 90% in the range of 3.13–4.42 GHz. For demonstration, adequate consistency between the simulation results and the measurement results was achieved. The proposed DRA has great application potential and value in 5G communication scenarios requiring wideband and high-gain antenna.

A 90° Twisted Quarter-Sectored Compact and Circularly Polarized DR-Rectenna for RF Energy Harvesting Applications

Radio frequency (RF) energy harvesting is the most adopted technique for replacing conventional batteries. However, the available RF energy in the surrounding atmosphere is low and unstable, so the antenna with high gain and polarization-insensitive characteristics is desired to collect a massive amount of power from the low-density environment. A 90° twisted quarter sectored circularly polarized and high gain dielectric resonator antenna (DRA) operating within the 5.8 GHz Wi-Fi band, is investigated first time of its kind in this letter. A circular-shaped aperture coupled feeding approach is investigated for energizing the proposed antenna. A metallic strip is placed on the right face of the optimized DRA for creating circular polarization characteristics. The optimized antenna (0.67 λ×0.67 λ×0.029 λ) offers a gain value of 7.02 dBc at 5.8 GHz frequency. A shunt-diode rectifier circuit is implemented for rectification purposes. The power conversion efficiency achieved at the operating frequency is 72.5% for an input power level of 5.75 dBm.

Gain Enhancement of Dielectric Resonator Antenna Using Electromagnetic Bandgap Structure

High gain antennas are highly desirable for long-range wireless communication systems. In this paper, a compact, low profile, and high gain dielectric resonator antenna is proposed, fabricated, experimentally tested, and verified. The proposed antenna system has a cylindrical dielectric resonator antenna with a height of 9 mm and a radius of 6.35 mm as a radiating element. The proposed dielectric resonator antenna is sourced with a slot while the slot is excited with a rectangular microstrip transmission line. The microstrip transmission line is designed for a 50 Ω impedance to provide maximum power to the slot. As a result, the proposed antenna operates at 5.15 GHz with a 10-dB absolute bandwidth of 430 MHz (4.98 – 5.41 GHz). It is important to mention that the gain of the dielectric resonator antenna is enhanced by the introduction of an electromagnetic bandgap (EBG) structure. In fact, EBG units are placed below the antenna, which enhances the realized peak gain from 5.32 dBi to 8.36 dBi at 5.15 GHz. More specifically, a gain enhancement of 3.04 dB is observed with the introduction of the EBG array. This antenna has several good features such as high gain, compact size, large bandwidth, and lower losses which make it a suitable choice for long-range wireless communication systems.

Synthesizing Radiation Properties of Dual-band Dual-mode High Gain Dielectric Resonator Antenna for Wireless Applications

Synthesizing Radiation Properties of Dual-band Dual-mode High Gain Dielectric Resonator Antenna for Wireless Applications

Cylindrical air spaced high gain dielectric resonator antenna for ultra-wideband applications

A new geometry of ultra-wideband (UWB) hollow dielectric resonator antenna (DRA) has been designed, simulated, and fabricated. The antenna consists of a rectangular dielectric resonator and excited by a transformer type microstrip feedline. A hollow cylindrical-shaped structure is extracted from a rectangular DR to improve the gain and impedance bandwidth of the antenna. The present work shows that the shifting within the UWB range along with the gain enhancement is observed by increased diameter of the hollow structure and the use of defective ground structure in the ground plane. The antenna provides four different radiating modes, namely TE11δ at 3.8 GHz, TE22δ at 6.4 GHz, TE 23 Z at 8.8 GHz, and TE33δ at 10 GHz that support to give widen impedance bandwidth. The simulated and measured results are in good agreement as an impedance bandwidth of 104.09% (3.28 to 10.4 GHz) and 103.86% along with a peak gain of 7.2 dB.

A High-Gain Dielectric Resonator Antenna With Plastic-Based Conical Horn for Millimeter-Wave Applications

A novel high-gain dielectric resonator antenna, featuring a peak realized gain of 11.3 dBi over a fractional bandwidth of 16.6% around 30 GHz, is presented. The proposed antenna structure, excited by a slot-coupled microstrip line, is composed of a cylindrical dielectric resonator and of a truncated plastic-based conical horn useful to enhance the gain. An annular perturbation notch is realized in the dielectric horn to achieve a better focusing of the RF energy along the antenna boresight direction, while reducing the sidelobe levels (SSLs). The presented antenna design achieves SSLs below −10 dB for both the E - and H -plane so to meet the requirements of next-generation 5G wireless communication protocols and of low-cost satellite and mobile systems.

Wideband and high gain dielectric resonator antenna for 5G applications

In this paper, wideband high gain dielectric resonator antenna for 5G applications is presented. Higher order mode is exploited to enhance the antenna gain, while the array of symmetrical cylindrical shaped holes drilled in the DRA to improves the bandwidth by reducing the quality factor. The proposed DRA is designed using dielectric material with relative permittivity of 10 and loss tangent of 0. 002.The Rogers RT/Droid 5880 has been selected as substrate with relative permittivity of 2.2, loss tangent of 0.0009- and 0.254-mm thickness. The simulated results show that, the proposed geometry has achieved a wide impedance bandwidth of 17.3% (23.8-28.3GHz=4.5 GHz) for S11-10 dB, and a maximum gain of about 9.3 dBi with radiation efficiency of 96% at design frequency of 26 GHz. The DRA is feed by microstrip transmission line with slot aperture. The reflection coefficient, the radiation pattern, and the antenna gain are studied by full-wave EM simulator CST Microwave Studio. The proposed antenna can be used for the 5G communication applications such as device to device communication (D2D).

Miniature high gain slot-fed rectangular dielectric resonator antenna for IoT RF energy harvesting

Radio-frequency (RF) energy harvesting is a promising candidate for alternative power source that can reduce the dependencies on batteries. However, its power density is very low which makes it crucial to have a high gain antenna to increase the power received by the system. This study presents the design of miniature high gain dielectric resonator antenna for RF energy harvesting application with high figure of merit to increase the power received. Numerical approximation is used to assist the antenna design and modelling. The design focused on three parameters which are the width, length, and height of the dielectric resonator. The performance, electric field density, and the radiation patterns of the dielectric resonator antenna have been observed by varying the design parameters. The effect of air gap to the performance is investigated and it is found that 8.11–13% gain improvement and up to 36% improvement in impedance matching is achieved through incorporating thin air gap between the dielectric resonator. Soda-lime glass with relative permittivity 7.75 is used which allows miniaturization and transparency. Experimental results show reasonable agreement to the simulations. The work shows highest antenna gain with smallest size with high FOM at 5 GHz ISM band compared to previous works.

A wideband high gain dielectric resonator antenna for RF energy harvesting application

A novel high gain and broadband hybrid dielectric resonator antenna (DRA) is designed and experimentally validated. To obtain the wide impedance bandwidth, the proposed antenna geometry combines the dielectric resonator antenna and an underlying slot with a narrow rectangular notch, which effectively broadens the impedance bandwidth by merging the resonances of the slot and DRA. An inverted T-shaped feed line is used to excite both antennas, simultaneously. It supports amalgamation of different resonant modes of the both, DRA and slot antenna. The measured results show that the proposed antenna offers an impedance bandwidth of 120% from 1.67 to 6.7GHz. The antenna gain is next enhanced by a reflector placed below the antenna at an optimum distance. On engineering the height and dimension of this reflector the antenna gain is improved from 2.2dBi to 8.7dBi at 1.7GHz. Finally, antenna operation is attested experimentally with a rectifier circuit in the frequency range of 1.8–3.6GHz, where various strong radio signals are freely available for RF energy harvesting. The measured maximum efficiency of the rectifier and rectenna circuit were found to be 74.4% and 61.4%, respectively.

Wideband Cylindrical Dielectric Resonator Antenna Operating in HEM11δ Mode with Improved Gain: A Study of Superstrate and Reflector Plane

A wideband and high gain dielectric resonator antenna (DRA) operating in hybrid HEM11δ mode is proposed. The investigated geometry employs one cylindrical dielectric resonator partially covered with a transparent dielectric superstrate and backed up by a single side metal coated dielectric reflector plane. The reflector is dedicated for gain enhancement while the superstrate is employed for merging of two resonant bands resulting in a single wide band. The dielectric resonator is excited by simple microstrip feed slot coupling technique and operates over X-band, ranging from 7.12 GHz to 8.29 GHz, that is, of 15.18% impedance matching bandwidth with 11.34 dBi peak gain. The different development stages like standalone DRA, DRA with superstrate, DRA with reflector, and DRA with both superstrate and reflector plane with respect to bandwidth and gain performances are analyzed properly. To the best of authors’ knowledge, this is the first time this type of combination of both superstrate and reflector plane is demonstrated in DRA engineering. An antenna prototype was fabricated and characterized and a very good agreement is achieved between the simulated and measured results.

A Low-Profile Stacked Dielectric Resonator Antenna With High-Gain and Wide Bandwidth

A wideband, low profile and high gain dielectric resonator antenna is investigated in this letter. The antenna consists of two dielectric layers with different permittivities and it is centrally fed by a rectangular slot. By placing the dielectric layer of low permittivity (2.2) below that of high permittivity (15), the antenna with low profile of $0.1{\lambda _0}$ can obtain a 10-dB impedance bandwidth of $\sim 40\% $ and an average gain of $\sim 9~\hbox{dBi}$ .

Enhanced-Gain Dielectric Resonator Antenna Based on the Combination of Higher-Order Modes

The combination of two higher-order hybrid electromagnetic modes ( ${{\rm HEM}_{133}}$ and ${{\rm HEM}_{123}}$ ) in a simple cylindrical dielectric resonator is exploited in the presented letter to enhance antenna gain. Both modes were excited by the same feeding aperture in the ground plane of a microstrip line. A linearly polarized, broadside radiation pattern with maximum realized gain of about 11.6 dBi was successfully obtained. The antenna was designed for the ISM band with central frequency 5.8 GHz and relative bandwidth of at least 2.6%. For fabrication, we used a layered Arlon AR600 substrate of relative permittivity 6.15. Experimental results showed reasonable agreement with simulations and validated the new concept of the high-gain dielectric resonator antenna.

A WIDEBAND HIGH-GAIN STACKED CYLINDRICAL DIELECTRIC RESONATOR ANTENNA

A new wideband and high-gain dielectric resonator antenna (DRA) is proposed. Three cylindrical dielectric resonators (DRs) with difierent materials and difierent sizes and a metallic cylinder are designed to obtain a wideband bandwidth and a high gain. The stacked structure provides a wideband bandwidth, and the cavity formed by the metallic cylinder provides a high gain. The measured results demonstrate that the proposed DRA has a wide bandwidth from 5.4 to 7.0GHz with VSWR less than two and a gain around 11dBi, covering the frequency range of 26%. The experimental and numerical results are discussed and compared with each other, showing a good agreement between them.

Design of High Gain and Broadband Antennas at 60 GHz for Underground Communications Systems

A new broadband and high gain dielectric resonator antenna for millimeter wave is presented. The investigated antenna configuration consists of a periodic square ring frequency selective surfaces on a superstrate, an aperture-coupled scheme feed, an intermediate substrate, and a cylindrical dielectric resonator. This antenna is designed to cover the ISM frequency band at 60 GHz (57 GHz–64 GHz). It was numerically designed using CST microwave Studio simulation software package. Another prototype with a plain dielectric superstrate is also studied for comparison purposes. A bandwidth of 13.56% at the centered frequency of 61.34 GHz and a gain of 11 dB over the entire ISM band have been achieved. A maximum gain of 14.26 dB is obtained at 60 GHz. This is an enhancement of 9 dB compared to a single DRA. HFSS is used to validate our antenna designs. Good agreement between the results of the two softwares is obtained. With these performances, these antennas promise to be useful in the design of future wireless underground communication systems operating in the unlicensed 60 GHz frequency band.