Dielectric Resonator Antenna Array Research Articles

Design and Performance Analysis of Dielectric Resonator Antenna Array for 5G mm-Wave Ground-Based Navigation and Wireless Applications

Design and Performance Analysis of Dielectric Resonator Antenna Array for 5G mm-Wave Ground-Based Navigation and Wireless Applications

Analysis of 3D Printed Dielectric Resonator Antenna Arrays for Millimeter-Wave 5G Applications

This paper explores the potential use of fused deposition modeling (FDM) technology for manufacturing microwave and millimeter-wave dielectric resonator antennas (DRAs) for 5G and beyond communication systems. DRAs operating at microwave and millimeter-wave (mmWave) frequency bands were simulated, fabricated, and analyzed in terms of manufacturing quality and radio frequency (RF) performance. Samples were manufactured using a 3D printer and PREPERM® ABS1000 filament, which offers a stable dielectric constant (εr = 10 ± 0.35) and low losses (tan δ = 0.003) over wide frequency and temperature ranges. Surface profile tests and microscope measurements revealed discrepancies in the dimensions in the xy-plane and along the z-axis, consistent with the observed shift in resonant frequency. Despite these variations, reasonably good agreement between RF-simulated and measured results was achieved, and the DRA array successfully covered the intended mmWave band. However, challenges in achieving high precision may restrict applications at higher mmWave bands. Nevertheless, compared with conventional methods, FDM techniques offer a highly accessible and flexible solution with a wide range of materials for home and micro-manufacturing of mmWave DRAs for modern 5G systems.

A wideband dual-circularly polarized traveling wave dielectric resonator antenna array

ABSTRACT In order to meet the demand of high capacity and high speed transmission of satellite communication system, a wideband dual-circularly polarized dielectric resonator antenna (DRA) array is proposed based on the traveling wave principle. Four DRA elements with slot-coupling excitation are sequentially placed on the ground, and the feeding network is designed to realize the two orthogonal circular polarization radiation waves. A notched copper loop (NCL) around the antenna array is adopted to improve the radiation performance. Depending on the operation of the two ports, the NCL generates the induced currents which rotates clockwise/counterclockwise, increasing the axial ratio bandwidth. In order to further improve the gain stability, the copper sheets are embedded on the top surface of each radiation element, and the copper cylinders perturb the internal field distribution of the DRA to introduce higher-order modes. The measurement results show that the left-hand circular polarization and the right-hand circular polarization operating bandwidths are 11.8% (14.97–16.85 GHz) and 12% (14.91–16.82 GHz). The antenna gain achieves 9.0 dBic. This DRA array can be applied for the vehicle mounted RF terminals in satellite communication.

Achieving high efficiency and bandwidth enhancement of DRA arrays: Synergic effects of LiMg4AlO6 microwave dielectric ceramic and 2D metamaterials

In this paper, LiMg4AlO6 ceramics with a sintering temperature of 1380 °C to 1460 °C are prepared, and the microwave dielectric properties of the ceramics and their potential application in dielectric resonator antenna (DRA) arrays are investigated. Analysis techniques such as XRD and Rietveld refinement reveal that the LiMg4AlO6 ceramics are rock salt structures and the space group is Fm-3 m (225). The ceramic obtained excellent microwave dielectric properties (εr = 10.17, Q×f = 172, 558 GHz, and τf = - 32.5 ppm/ °C) at 1440 °C. The εr of LiMg4AlO6 ceramics exhibits minimal variation across a wide temperature range (-100 °C to 400 °C) without phase transition. Furthermore, the 2D metamaterials (metasurfaces) are introduced in the DRA, which can significantly improve the radiation efficiency and bandwidth of the antenna. Measured results demonstrate that the antenna has a wide bandwidth ranging from 8.07 GHz to 8.57 GHz, with a maximum realized gain of 8.9 dBi and a peak radiation efficiency of 97%. The proposed ceramic antenna array combines the superior properties of 2D metamaterials and ceramic materials, which opens up a new avenue for ceramic antenna design and satellite communication applications.

Time-modulated planar frequency diverse array for multi-target detection

The frequency diverse array (FDA) is a very interesting technique in wireless communications. Many research papers are introduced in this field. A lot of them is concerned with linear point sources array. In this paper, a design of a time-modulated planar frequency diverse array architecture is proposed for tracking single or multi-target for the first time. The time-modulation array (TMA) and FDA are combined for detecting single and multi-target. The effectiveness of this combined scheme is demonstrated through simulation results that compared with a point source case to show its superior performance. Authors introduce planar FDA array instead of linear FDA array and realize the planar array using cylindrical dielectric resonator antenna array (CDRA). A planar array consists of 8 × 8 CDRA is used to enable the detection of single target/multi-target. The operating frequency of the antenna is set at 10 GHz, aligning with its applications in the FDA radar. The radiation characteristics of the CDRA antenna element are introduced. High maximum gain of 6 dBi is achieved with a remarkably high efficiency. A set of representative results is reported and analyzed to assess the effectiveness of the proposed approach.

Design of Self-Decoupled Circularly Polarized MIMO Dielectric Resonator Antenna Arrays Based on Polarization Orthogonality

Design of Self-Decoupled Circularly Polarized MIMO Dielectric Resonator Antenna Arrays Based on Polarization Orthogonality

Wideband Circularly Polarized Substrate Integrated Dielectric Resonator Antenna Array for 5G Millimeter-Wave Applications

Wideband Circularly Polarized Substrate Integrated Dielectric Resonator Antenna Array for 5G Millimeter-Wave Applications

Design and optimization of circularly polarized dielectric resonator antenna array based on Al2O3 ceramic

A comprehensive design of an ultra-broadband circularly polarized (CP) dielectric resonator antenna (DRA) array operating in the C-band for fifth-generation (5G) communication systems is presented in this paper. The objective is to achieve a compact antenna size capable of receiving and transmitting CP electromagnetic waves over a wider bandwidth. The material chosen for the dielectric resonator (DR) is Alumina (Al2O3) ceramic, known for its low dielectric loss and exceptional mechanical properties, making it an ideal candidate for the DR. The proposed design utilizes a 2 × 2 array of cross-shaped DRs, fed by a compact circular phase-shift feeding network with double-point feeding. This configuration results in a 3-dB axial ratio (AR) bandwidth of 48.7 % and an impedance matching bandwidth (IMB) of 53.2 %. The antenna's horizontal size is reduced to 1.17 × 1.17λ02, and the gain is significantly enhanced by exciting multiple Mie resonances in the stacked DRs, yielding a measured peak gain of 12.48 dBic. These outstanding features position the CP DRA array as an excellent choice for 5G communication systems.

Wideband millimeter-wave hybrid dielectric resonator antenna array with dual-slot feeding

ABSTRACTA hybrid dielectric resonator antenna (DRA) array is proposed for the wideband millimeter-wave communication. The radiator is composed with a pair of stacked dielectric resonators (DRs), which are H-shaped and Hexagon-shaped DRs, respectively. The dual-slots on the substrate integrated waveguide (SIW) cavity are utilized for higher mode generation in the DRA element. The antenna bandwidth is improved by the stacked DRs and dual-slot feeding. The structural characteristics and key parameters of feeding slots are discussed in detail. The DRA array fed with parallel power distribution feeding network is fabricated and measured to verify the reliability of the simulations, and the simulations and measurements have reasonable consistency. The impedance bandwidth is from 23.55 GHz to 27.28 GHz (14.7%), and the measured gain ranges from 13.1 dBi to 15.7 dBi. The radiation patterns are stable in the operation band. The proposed DRA array has a promising application prospect for 5 G communication system.

A Self-Decoupling Method for MIMO Linear and Planar Dielectric Resonator Antenna Arrays Based on Transmission Characteristics of Feeding Structure

In this paper, a novel self-decoupling method for the multi-input multi-output (MIMO) dielectric resonator antenna (DRA) arrays is investigated. This method is based on the transmission characteristics of the conformal strip that feeds the DRA. It is found that when the strip-fed DRA operates in the higher-order mode, e.g., TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">113</sub> mode, the E-field coupled to the metal strip of the adjacent passive DRA presents a standing wave distribution. By appropriately adjusting the dimensions of the feeding strip, the E-field can form a node with zero amplitude at its bottom where a coaxial probe is connected, preventing the energy from getting into the receiving port and hence achieving a high isolation level without requiring any extra decoupling structure. This self-decoupling method is applicable not only to one-dimensional (1-D) H- and E-plane coupled MIMO linear arrays but also to two-dimensional (2-D) MIMO planar array. To verify its feasibility, a prototype of 2 × 2 MIMO planar DRA array is simulated, processed, and tested. The results show that a usable bandwidth (|S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ii</sub> | < -10 dB and |S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ij</sub> | < -20 dB) of 10.8% is achieved, and the maximum isolation is over 40 dB within the passband.

1-D Wideband Phased Dielectric Resonator Antenna Array With Improved Radiation Performance Using Characteristic Mode Analysis

A 1-D wideband phased array of the rectangular ring dielectric resonator antenna (RRDRA) is presented for millimeter-wave applications. By using the characteristic mode analysis, it is found that the unwanted higher order mode (HOM) of the RRDRA results in severe gain degradation and high cross polarization when the array scans. To remedy the problem, each RRDRA is loaded with a pair of silver strips. They can suppress the unwanted HOM and enable good scanning performance in a wide frequency range. To demonstrate the idea, a 1×4 phased RRDRA array was designed, fabricated and measured for the licensed millimeter-wave bands (24.25–29.5 GHz). Reasonable agreement between the measured and simulated results is observed.

Wideband Circularly Polarized Millimeter-Wave DRA Array for Internet of Things

This work proposes a novel millimeter-wave wideband circularly polarized antenna array for Internet of Things (IoT) applications. The proposed design addresses the issues of having IoT sensors deployed in remote locations or over large geographical regions. Elliptically-shaped dielectric resonator antennas (DRAs) are used as array elements to improve radiation characteristics and achieve circular polarization over a wide impedance bandwidth around 28 GHz. Two different sequential-phase corporate feed networks are studied and compared to obtain wider impedance, 3-dB gain, and axial ratio (AR) bandwidths. Furthermore, a ridge gap waveguide technique based on the low-cost PCB technology is adopted to reduce the transmission losses in the considered sequential-phase feed networks. The proposed millimeter-wave antenna exhibits an impedance bandwidth of 35% (28.1-40 GHz) and 3-dB gain bandwidth of 19.3% (27.6-33.5 GHz). The achieved 3-dB AR bandwidth is 22.6% (27.5-34.5 GHz). The proposed antenna was fabricated and measured, and good agreement between measured and simulated results was obtained. The reported results show that the suggested wideband circularly polarized millimeter-wave antenna has a lot of promise in preventing polarization mismatch losses between IoT devices and satellites caused by their varying orientations.

A Compact Aperture-Sharing Sub-6 GHz/Millimeter-Wave Dual-Band Antenna.

In this article, a microwave (MW)/millimeter wave (MMW) aperture-sharing antenna is proposed. The antenna is constructed using two orthogonal columns of grounded vias from a 3.5 GHz slot-loaded half-mode substrate-integrated waveguide (HMSIW) antenna. These vias are reused to create two sets of 1 × 4 MMW substrate-integrated dielectric resonator antenna (SIDRA) arrays. With this proposed partial structure reuse strategy, the MW antenna and MMW arrays can be integrated in a shared-aperture manner, improving space utilization and enabling dual-polarized beam steering capability in the MMW band, which is highly desirable for multiple-input multipleoutput (MIMO) applications. The integrated antenna prototype was manufactured and measured for verification. The 3.5 GHz antenna has a relative bandwidth of 3.4% (3.44-3.56 GHz) with a peak antenna gain of 5.34 dBi, and the 28 GHz antenna arrays cover the frequency range of 26.5-29.8 GHz (11.8%) and attain a measured peak antenna gain of 11.0 dBi. Specifically, the 28 GHz antenna arrays can realize dual-polarization and ±45° beam steering capability. The dual-band antenna has a very compact structure, and it is applicable for 5G mobile communication terminals.

A Low-Profile Dielectric Resonator Antenna Array for OAM Waves Generation at 5G NR Bands.

This paper presents the generation of orbital angular momentum (OAM) vortex waves with mode +1 using dielectric resonator antenna (DRA) array. The proposed antenna was designed and fabricated using FR-4 substrate to generate OAM mode +1 at 3.56 GHz (5G new radio band). The proposed antenna consists of 2 × 2 rectangular DRA array, a feeding network, and four cross slots etched on the ground plane. The proposed antenna succeeded in generating OAM waves; this was confirmed by the measured radiation pattern (2D polar form), simulated phase distribution, and intensity distribution. Moreover, mode purity analysis was carried out to verify the generation of OAM mode +1, and the purity obtained was 53.87%. The antenna operates from 3.2 to 3.66 GHz with a maximum gain of 7.3 dBi. Compared with previous designs, this proposed antenna is low-profile and easy to fabricate. In addition, the proposed antenna has a compact structure, wide bandwidth, high gain, and low losses, thus meeting the requirements of 5G NR applications.

Multi-feed, loop-dipole combined dielectric resonator antenna arrays for human brain MRI at 7 T

ObjectiveTo determine whether a multi-feed, loop-dipole combined approach can be used to improve performance of rectangular dielectric resonator antenna (DRA) arrays human brain for MRI at 7 T.Materials and methodsElectromagnetic field simulations in a spherical phantom and human voxel model “Duke” were conducted for different rectangular DRA geometries and dielectric constants εr. Three types of RF feed were investigated: loop-only, dipole-only and loop-dipole. Additionally, multi-channel array configurations up to 24-channels were simulated.ResultsThe loop-only coupling scheme provided the highest B1+ and SAR efficiency, while the loop-dipole showed the highest SNR in the center of a spherical phantom for both single- and multi-channel configurations. For Duke, 16-channel arrays outperformed an 8-channel bow-tie array with greater B1+ efficiency (1.48- to 1.54-fold), SAR efficiency (1.03- to 1.23-fold) and SNR (1.63- to 1.78). The multi-feed, loop-dipole combined approach enabled the number of channels increase to 24 with 3 channels per block.DiscussionThis work provides novel insights into the rectangular DRA design for high field MRI and shows that the loop-only feed should be used instead of the dipole-only in transmit mode to achieve the highest B1+ and SAR efficiency, while the loop-dipole should be the best suited in receive mode to obtain the highest SNR in spherical samples of similar size and electrical properties as the human head.

An eight‐element sequentially rotated crescent‐slot‐coupled dielectric resonator antenna array for WIFI applications

SummaryIn this communication, the author presents an eight‐element sequentially rotated (SR) circularly polarized (CP) dielectric resonator antenna (DRA) for operation in the IEEE 802.11a standard. A novel resonating element composed of a crescent slot (CS) used to excite a rectangular dielectric resonator (RDR) is proposed that has two orthogonal modes and as required for CP radiation. An SR series–parallel geometry is used to prototype the array feed network to allocate the array elements to symmetrical positions. The phase progression of each element was 45° along the array, and the signal magnitude was distributed evenly based on the binomial theory to enhance the antenna performance. The prototyped SR array had a size of mm3 and was measured and characterized in order to authenticate the design. The resonance bandwidth (S11 ˂ −10 dB) was found to be 14.28% with a 3 dB axial ratio (AR) of 17.7% for right‐hand CP. The gain varied from 15.71 to 16.26 dBi within the operating band. The size, gain, and impedance bandwidth of the proposed array make it a potential candidate for devices operating in the IEEE 802.11a band.

Fabrication of High Radiation Efficiency Dielectric Resonator Antenna Array Using Temperature Stable 0.8Zn2SiO4‐0.2TiO2 Microwave Dielectric Ceramic

AbstractArray antenna is of great significance in realizing the Sub‐6 GHz fifth‐generation (5G) mobile communication systems, however, its utilization in the base station systems implementation is limited due to high power consumption. In this paper, a high radiation efficiency 4 × 4 cylindrical dielectric resonator antenna (CDRA) array fabricated using the temperature stable 0.8Zn2SiO4‐0.2TiO2 composite ceramic is proposed. TiO2‐doped Zn2SiO4 composite ceramics are synthesized by the conventional solid‐state method. Notably, 0.8Zn2SiO4‐0.2TiO2 composite ceramic sintered at 1250 °C demonstrates excellent microwave dielectric properties with dielectric constant (εr ≈ 8.24), high‐quality factor (Q × f ≈ 35 000@8.08GHz), and the temperature coefficient of resonant frequency (TCF ≈ +4.6 ppm °C−1). Moreover, the composite ceramic CDRA array is designed by exciting fundamental HE11δ mode using the aperture coupling microstrip feeding network. The fabricated composite ceramic based 4 × 4 CDRA array has enhanced measured radiation efficiency of up to 87%, high gain of 17.85 dBi and is a promising candidate for utilization in Sub‐6 GHz 5G Base Station communications systems.

5G MILLIMETER WAVE MIMO DIELECTRIC RESONATOR ANTENNA

A four-element rectangular dielectric resonator antenna (DRA) array for fifth generation (5G) multiple-input-multiple-output (MIMO) application at 28 GHz is presented. Each DRA element of the array has a very small dimension of 3 &amp;times; 0.03 &amp;times; 6 mm and oriented at an angle of 90 deg to each other. Total dimension of the proposed antenna system is 20 &amp;times; 20 &amp;times; 7 mm. Each antenna of the system has high radiation efficiency (&amp;#60; -0.004 dB). Defected ground structure is used to obtain very good isolation (&amp;#62; 27 dB) between any two DRA elements of the array. Moderate directivity (&amp;#62; 4.1 dBi) of the MIMO antenna can be increased up to 7.8 dBi using thin metal walls to separate each DRA element of the system. This MIMO antenna system is capable of giving 4 GHz impedance band width extending from 25.78 to 29.78 GHz. Computer simulation technology is used to design and investigate the performance parameters of this MIMO antenna system. Performance parameters of the proposed antenna are compared with similar types of antennas found in recent literature.

Wideband Low-Profile Connected Rectangular Ring Dielectric Resonator Antenna Array for Millimeter-Wave Applications

A wideband low-profile connected rectangular ring dielectric resonator (DR) antenna (DRA) array is presented for millimeter-wave (mmWave) applications. It consists of four rectangular ring DRA elements. The DRA elements are excited by microstrip feedlines through four slots on the ground plane. A slot mode, the DRA <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}^{\text {y}}_{1\delta 1}$ </tex-math></inline-formula> mode, and the perturbed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}^{\text {y}}_{3\delta 1}$ </tex-math></inline-formula> mode are simultaneously excited, giving a wideband design. To avoid the alignment problem, the DRAs are connected to their adjacent elements through dielectric arms. It is found that the position of the dielectric arms has significant effects on the antenna performance. To demonstrate the idea, a prototype with a dielectric constant of 20.8 was designed, fabricated, and tested for licensed mmWave bands (24.25–29.5 GHz). A reasonable agreement between the measured and simulated results is observed. The measured 10 dB impedance bandwidth ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert \text{S}_{11}\vert \le - 10$ </tex-math></inline-formula> dB) is 31.6% (22.52–30.97 GHz), with a measured boresight realized gain being higher than 8 dBi from 22.5 to 30 GHz. The measured mutual couplings between the DRA elements of the array are lower than −20 dB in the operating frequency range. Furthermore, our prototype has a low profile of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.074~\lambda _{0}$ </tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> is the wavelength in air at the center frequency.

A Low-profile 4-element Circularly Polarized Hexagonal DRA Array for Triple-band Wireless Applications

This paper presents a triple-band low-profile circularly polarized (CP) hexagonal dielectric resonator antenna (HDRA) array for various wireless applications. A 4-element linear array is designed using a simple microstrip power divider to improve the performance of the HDRA. This HDRA excites TEd01 mode at a first resonant frequency of 1.52 GHz. The proposed design operates in three frequency bands, i.e. 1.44 - 1.61 GHz, 2.95 - 3.27 GHz, and 4.00 - 4.84 GHz with the fractional bandwidth of 10.98%,11.02% and 22.20%, respectively. It also provides good gain and more than 70% of radiation efficiency with a better radiation pattern at all the resonating points. Further, it has a CP bandwidth of 50 MHz and 650 MHz around 3.12 GHz and 4.25 GHz, respectively. The proposed HDRA array is suitable for different wireless applications such as GPS (1 - 2 GHz), WiMAX (2 - 4 GHz), and WLAN (4 - 8 GHz).