Abstract In this article, a circularly polarized dielectric resonator antenna (DRA) array with conformal characteristics and improved specific absorption rate (SAR) has been proposed for X-band applications. The proposed structure has been fed through the corporate feed network which excites a radiating mode inside DRA, i.e., $TE_{1\delta1}$ . This mode has been utilized to enhance the impedance bandwidth which is below −10 dB for both the E- and H-plane so as to meet the requirements of next-generation defense communication and low-cost satellite systems. To generate the axial ratio (AR), the extended off-set feed has been employed to provide the required 90 $^{\circ}$ phase shift. Further, in order to enhance the gain and reduce the SAR, an electromagnetic band gap structure has been used as a reflector. Furthermore, multiple arrays have been introduced to extend the coverage area through beam-forming. The proposed design has been fabricated for the experimental validation. The measured IBW and ARBW is 34.74% and 12.2%, respectively. The gain is 10.1 dBic throughout the band of operation along with the radiation efficiency above 85% in various bending conditions. The SAR is much below the permissible limit of 1.6 W/kg. Thus, the proposed array is compact, and it clearly achieves a smaller footprint, better IBW, ARBW and a low SAR with potential prospect for X-band purposes.

Abstract Modern wireless communication systems include phased array antennas as essential components. Cylindrical Dielectric Resonator Antenna (CDRA) arrays on planar ground planes are widely explored. Conformal arrays have several advantages over flat arrays, including reduced aerodynamic drag, and wider coverage angles. Therefore, a conformal phased array CDRA is proposed in this paper. For efficient radiation, a CDRA fed by a rectangular slot aperture coupled feed excites the HEM 11δ mode. For obtaining a higher directive gain, a 1 × 4 CDRA array is designed. 5 dBi improvement in gain is obtained by a 1 × 4 CDRA array. A cylindrically conformal phased array, placed on a 360 mm radius cylindrical surface, is presented for wide beam scanning. The impedance bandwidth obtained for the proposed conformal CDRA array is 22% which ranges from 7.6 to 9.5 GHz. The proposed array can scan from −25° to +25° with a gain fluctuation of less than 4 dBi. Within the impedance bandwidth, the isolation between neighboring elements is less than −25 dB. The peak gain of the conformal CDRA array is 10.2 dBi at a frequency of 8.7 GHz. The efficiency of the antenna is more than 91% for the whole band. Additionally, with a height of 0.08 λ 0 , the 1 × 4 CDRA array has a low profile which offer significant benefits in advanced packaging. The study that is being proposed finds applications for conformal platforms in high-speed vehicles, missiles, and aircraft.

ABSTRACT A highly integrated circularly polarized (CP) filtering dielectric resonator antenna (DRA) array based on a folded helical structure is proposed in this paper. The antenna element mainly consists of a half-wavelength folded metal helical strip and a hollow cylindrical dielectric resonator. The Hybrid Electric Magnetic (HEM) mode of the DRA can be regarded as an equivalent magnetic current (MC), which is excited by the electric current (EC) on the helical strip. Based on the magneto-electric currents combination (MECC) method, MC and EC with appropriate amplitude ratio and phase difference are designed to realize CP performance. According to the fusion method, an electromagnetic coupling excitation structure combining substrate integrated waveguide (SIW) and embedded coplanar waveguide (CPW) is adopted to regulate the internal field resonance mode of the SIW cavity, enabling the antenna to successfully possess bandpass filtering characteristics. The antenna element is excited by a microstrip power divider above the slot and expanded into a 2 × 2 array. The prototype of the antenna has been fabricated, and measured results demonstrate that the proposed antenna has a relative impedance bandwidth of 11.2% and an axial ratio bandwidth of 6.2%, with radiation nulls at both sides of the passband. Measurement results show gains of 7.42 dBi (element) and 9.28 dBi (2 × 2 array). The proposed antenna is suitable for ground-based equipment in C-band satellite communication systems.

Abstract This research introduces a coplanar waveguide (CPW)-coupled single cylindrical dielectric resonator antenna (SCDRA) and expands the investigation to a four-element linear array circular dielectric resonator antenna (LACDRA) to improve performance at terahertz (THz) frequencies. The design is optimized for functioning at around 4 THz, with supplementary resonances detected at 5 THz, 6 THz, and higher frequencies. The research encompasses a parametric examination of substrate thickness and its effects on resonant frequency and impedance matching. The singular DRA design exhibits multiple mode excitation, encompassing HEM11, TM110, and TE111, which enhances operational bandwidth and ensures consistent gain performance. The radiation properties of SCDRA demonstrate peak gains of 6.16 dB, 7.04 dB, and 8.31 dB at frequencies of 4 THz, 5 THz, and 6 THz, respectively. A four-element LACDRA design is presented to enhance directivity and gain. The LACDRA demonstrates a maximum gain of 10.88 dB at 4.5 THz, featuring improved polarization purity and less cross-polarization losses. The results indicate that CPW-fed DRAs are exceptionally appropriate for THz wireless communication, imaging systems, and bio-sensing applications, providing a small, efficient, and broadband solution.

Abstract In this communication, a 2 × 2 polarization reconfigurable (PR) sequentially rotated (SR) dielectric resonator antenna (DRA) array is presented to resonate within the IEEE 802.11a band. The array is formed of a novel resonator composed of a rectangular dielectric resonator (RDR) excited by a copper strip of hooked T‐shaped monopole to excite two degenerate resonant modes and confirming the circular polarization (CP) radiation. The proposed resonating element is optimized to operate at 5.8 GHz with the RDR dimensions being 10 × 5 × 10 mm3. A 2 × 2 array which is formed of the proposed resonator with a feeding circuit constitutes a single Wilkinson power divider (WPD), a single out‐of‐phase Schiffman coupler, and couple quartile branch line couplers (BLC). The polarization reconfigurability is obtained using positive–intrinsic–negative (PIN) diodes located at the BLC inputs as current switches. With proper PIN diodes switching, the radiated fields can be set to either right‐hand circular polarization (RHCP) or left‐hand circular polarization (LHCP). To investigate the initiated array resonance performance, an equivalent impedance circuit of the postulated array is proposed based on the array sub‐components’ equivalent lumped elements before simulation and measurements. The 100 × 40 mm2 array possessed an impedance bandwidth of 12.07% for RHCP and 12.03% for LHCP within the IEEE 802.11a band. The maximum realized gain was 8.31 dBi with axial ratio (AR) bandwidth of 12.04%. The obtained results verified that the suggested array can emit two CP conditions with reasonable accord between the simulated and measured ones.

Abstract This article presents two high-gain and wideband antenna arrays for 5G NR (new radio) bands n257/n258/n261 (24.25–29.5 GHz). A novel substrate integrated waveguide feeding approach for linear dielectric resonator antenna arrays is employed to excite array elements. This new design approach is straightforward, compact, and inexpensive. The incorporation of metallic patches on the cubical dielectric resonator antenna faces and perforation is implemented to enhance the working band. The dimensions of the proposed array for series orientation are 34.9x8.4x3.85mm3 whereas the corporate array is 27.6x22.7x3.85mm3. Both arrays consist of four elements that exhibit a measured impedance bandwidth of 21.1% to 35.6%, with a peak gain between 10 to 14 dBi and total efficiency above 91%. Compared to state-of-the-art feeding techniques, the suggested method delivers greater gain, elevated bandwidth, and improved efficiency with a compact electrical size.

Circularly polarized dielectric resonator antenna array with filtering characteristics

To address the inherent contradiction between low-profile design and high gain in traditional omnidirectional antennas, as well as the narrow bandwidth constraints of ENZ antennas, this study presents a dual-mode ENZ-FP collaborative resonant antenna array design utilizing a substrate-integrated waveguide (SIW). Through systematic analysis of ENZ media’s quasi-static field distribution, we innovatively integrated it with Fabry–Perot (F–P) resonance, achieving unprecedented dual-band omnidirectional radiation at 5.18 GHz and 5.72 GHz within a single ENZ antenna configuration for the first time. The directivity of both frequencies reached 12.0 dBi, with a remarkably low profile of only 0.018λ. We then extended this design to an ENZ-FP dual-mode beam-scanning array. By incorporating phase control technology, we achieved wide-angle scanning despite low-profile constraints. The measured 3 dB beam coverage angles at the dual frequencies were ±63° and ±65°, respectively. Moreover, by loading the impedance matching network, the −10 dB impedance bandwidth of the antenna array was further extended to 2.4% and 2.7%, respectively, thus overcoming the narrowband limitations of the ENZ antenna and enhancing practical applicability. The antennas were manufactured using PCB (Printed Circuit Board) technology, offering high integration and cost efficiency. This provides a new paradigm for UAV (Unmanned Aerial Vehicle) communication and radar detection systems featuring multi-band operation, a low-profile design, and flexible beam control capabilities.

79 GHz three stacked cylindrical dielectric resonator antenna array for automotive radar systems

In this article, a chip-fed millimeter-wave high-gain antenna system with in-antenna power combining capability is presented. A low-profile resonant cavity antenna (RCA) array is fed by multiple spherical dielectric resonators (DRs), demonstrating its multi-feed capabilities. Each of the DRs is fed by two microstrip resonators on a planar circuit board. A printed superstrate is used in the proposed RCA as the partially reflecting superstrate (PRS), which makes the antenna profile small. To increase the directivity and gain, a 2 × 2 RCA array is developed. The demonstrated design shows a prominent peak gain of 25.03 dBi, a radiation efficiency of more than 80% and 3.38 GHz 3 db gain-bandwidth while maintaining a low profile. To steer the beam of the demonstrated 2 × 2 RCA array in a wide angular range with a low side-lobe-level, two planar all-dielectric passive beam steering metasurfaces have been designed and optimized. A detailed analysis of the optimization procedure is presented in this article. This numerical investigation is vitally important for realizing beam steering metasurfaces with suppressed side-lobe-level, wide bandwidth, excellent efficiency and less complexity.

Cross-Functional Integration of Dielectric Resonator Bandpass Filter and Antenna Array with Low Insertion Loss and High Isolation

A Wideband Circularly Polarized Millimeter-Wave Dielectric Resonator Antenna Array with Reconfigurable Polarization State

A Broadband Dual-Polarized Meta-Dielectric Resonator Antenna Array

Design of a Seamlessly Integrated Dielectric Resonator Antenna Array with Self-Decoupling Property for Millimeter-Wave Applications

Sub-6 GHz Filtenna Integration With mm-Wave Dielectric Resonator Antenna Array for 5G Applications

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

ABSTRACT A circularly polarized (CP) filtering dielectric resonator antenna (DRA) array is proposed based on the magneto-electric currents combination (MECC) method in this paper. The array consists of four rectangular DRAs, four hook-shaped electric dipoles (HSED), and two layers of substrate integrated waveguide (SIW) cavities. The electric current (EC) on the HSED is excited by the slot aperture of the SIW cavity, and the equivalent magnetic current (MC) is simultaneously generated with HSED in the DRA. Based on the surface current regulation, the EC and MC are adjusted to achieve appropriate amplitudes and phases, thereby realizing wideband CP radiation. The filtering function is realized with the high-pass characteristics of the SIW and the effective suppression of the higher-order modes in the resonance cavity. Due to the presence of an air gap between the DRAs and HSED, the higher modes of the DRA are designed for bandwidth enhancement. The prototype of the DRA array has been fabricated and measured, exhibiting a relative bandwidth of 26.1% and an axial ratio bandwidth of 17.77%, with radiation nulls present at either side of the passband. With the advantages of wide bandwidth and high gain, the proposed DRA array can be applied to satellite communications.

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

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