Dual-polarized Dielectric Resonator Antenna Research Articles

High-Gain, Low-Coupling, Omnidirectional, and Dual-Polarized Dielectric Resonator Antenna Using High-Order Modes

High-Gain, Low-Coupling, Omnidirectional, and Dual-Polarized Dielectric Resonator Antenna Using High-Order Modes

MM-Wave High Isolated Dual Polarized Dielectric Resonator Antenna for In-Band Full-Duplex Systems

A novel high-isolation dual-polarized in-band full-duplex (IBFD) dielectric resonator antenna (DRA) for satellite communications using a decoupling structure is proposed. Good isolation between transmit and receive ports is achieved by placing two identical linearly polarized resonators orthogonal to each other. Each resonator consists of a main rectangular dielectric resonator of the dielectric constant of 10 and is loaded by a thin dielectric slab of lower permittivity of 5 to broaden the matching bandwidth further. The isolation is further improved by loading an absorber and etching several slots in the ground plane. Finally, the proposed DRA is fabricated and measured to validate the concepts. Measurement results show high isolation of more than 50 dB over the desired operating bandwidth from 23.04 GHz to 24.08 GHz (ka-band) with a peak gain of about 8.93 dBi and 8.09 dBi for Port 1 and Port 2, respectively. In addition, the proposed IBFD DRA provides 11.87 GHz and 4.84 GHz isolation bandwidths over 25 dB and 30 dB, respectively, making it a potential candidate for mm-wave terrestrial applications.

Differentially Fed Dual-Polarized 2-D Multibeam Dielectric Resonator Antenna Array Based on Printed Ridge Gap Waveguide

In this article, a differentially fed dual-polarized dielectric resonator antenna (DRA) subarray excited by a substrate integrated waveguide (SIW) cavity is proposed. A #-shaped slot etched on the top wall of the SIW cavity is used to achieve the differential excitation due to the intrinsic field distribution of TE120 mode in the SIW. Based on the proposed antenna subarray, a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times $ </tex-math></inline-formula> 2 dual-polarized 2-D multibeam DRA antenna array with simple structure is designed, fabricated, and measured, which can achieve high cross-polarization discrimination (XPD) in the direction of maximum radiation. To reduce substrate loss, the printed ridge gap waveguide (PRGW) technology is used to feed the SIW cavity. Two orthogonal PRGW Butler matrices are placed at different layers so as to realize 2-D beamforming scanning with dual-polarization. The SIW cavity is placed in the air gap of PRWG, which can increase the stability of the antenna structure. By cleverly combining the SIW cavity and PRGW structure, the proposed multibeam antenna array has the advantages of high XPD and high radiation efficiency. Measured results show that an impedance bandwidth of 10% (28.5–31.5 GHz) and a peak gain of 11.8 dBi are obtained. Also, the measured XPDs are 28.3 dB at the center frequency and larger than 19.2 dB over the band of operation. Besides, the measured radiation efficiency of 67% is achieved for both the polarizations at 30 GHz.

Wideband Substrate Integrated Differential Dual-Polarized Dielectric Resonator Antenna

A substrate integrated differential cavity-backed dual-polarized dielectric resonator antenna with a wide bandwidth, low profile, high isolation, and improved gain is presented. The proposed substrate integrated technique, in which the electric and magnetic walls of the cross-shaped dielectric resonator antenna (DRA) are realized by arrays of metallic and nonmetallic vias, respectively, provides the design with high level of integration and low profile. The substrate integrated DRA is differentially fed by microstrip lines through coupling slots exciting a pair of orthogonal modes for the dual polarizations. The differential feeding scheme offers a direct connection to differential systems, and greatly improves the isolation between polarizations. Benefitting from the differential coupling slots and the substrate integrated back cavity, the bandwidth is broadened and the realized gain is improved. For demonstration, a prototype is designed and fabricated. The simulated and measured results show a good agreement.

Frame Integrated Wideband Dual-Polarized Arrays for Mm-Wave/Sub 6-GHz Mobile Handsets and Its User Effects

In this work, wideband dual-polarized dielectric resonator antenna (DRA) arrays are designed for 5G mobile handsets and integrated with the sub-6GHz antenna. The dielectric resonators, surrounded by concentric air holes and metal vias, are excited by two orthogonal slots and fed through microstrip lines, providing a wide bandwidth from 25.3 GHz to 29.8 GHz. A high isolation of above 40 dB is obtained between the ports of the orthogonally polarized antennas. Based on the dual-polarized DRA, two 1 × 4 arrays are built and integrated with the longer metal frames of the handset, without occupying extra space on the chassis. The scanning angle for the proposed array is from 47° to 121° for the gain of above 10 dBi, and the overall handset antennas provide a large coverage efficiency of 80% for a threshold gain of 5 dBi. User effect has also been investigated, manifesting that the horizontally polarized antennas are less influenced by the hands in both the one-hand and the two-hand data modes. Furthermore, a sub-6GHz antenna is designed with a wide operating band from 0.7 GHz to 0.94 GHz simply by making use of the shorter frames and the dual-layered DRAs, with a small ground clearance of 2 mm remained. The performances of the arrays are validated by measuring the representative antennas. The proposed antenna is a good candidate for future handsets due to its high integration with the metal frames and with the LTE antenna, its large bandwidth and large coverage in free space and different user scenarios.

A Broadband Differential-Fed Dual-Polarized Hollow Cylindrical Dielectric Resonator Antenna for 5G Communications.

A broadband differential-fed dual-polarized hollow cylindrical dielectric resonator antenna (DRA) is proposed in this article. It makes use of the HEM111, HEM113, and HEM115 modes of the cylindrical hollow DRA. The proposed DRA is simply fed by two pairs of conducting strips and each pair of strips is provided with the out-of-phase signals. After introducing four disconnected air holes into the DRA, a broadband characteristic is achieved, with little effect on the antenna gain of its higher-order modes. To verify this idea, frosted K9-glass is applied to fabricate the hollow cylindrical DRA. The differential S-parameters, radiation patterns, and antenna gain of the DRA are studied. It is found that the proposed differential-fed dual-polarized DRA is able to provide a broad differential impedance bandwidth of ~68% and a high differential-port isolation better than ~46 dB. Moreover, symmetrical broadside radiation patterns are observed across the whole operating band. The proposed DRA covers the frequency bands including the 5G-n77 (3.4–4.2 GHz), 5G-n79 (4.4–5.0 GHz), WLAN-5.2 GHz (5.15–5.35 GHz), and WLAN-5.8 GHz (5.725–5.825 GHz), which can be used for 5G communications.

A mmW Broadband Dual-Polarized Dielectric Resonator Antenna Based on Hybrid Modes

This letter presents a dual-polarized dielectric resonator antenna (DRA) achieving more than 40% fractional bandwidth, thus the 5G bands n257 and n260 are covered with a single antenna. Hence, the system cost is considerably reduced, since only one antenna array system is required. The bandwidth could be reached thanks to the wideband monopoles and differential feeding enabling hybrid operation in monopole and DRA mode. The antenna uses a standard two metal layer printed-circuit-board (PCB) process and 3-D printing for the fabrication of the dielectric resonators, reducing the number of PCB layers and the overall production cost. The prototypes of a single element and 2 × 2 array show a maximal gain of 7.1 and 10.4 dBi, respectively.

An Enhanced Gain Dual-Polarized Dielectric Resonator Antenna Array with High Isolation for C-Band Applications

ABSTRACTThis article presents the design and performance analysis of a high gain dual-polarized two-element cylindrical dielectric resonator antenna (DRA) array excited by two orthogonally placed H-shaped apertures. The antenna is operated in dual linear polarized mode by exciting TM110 (HEM11) mode in two DRAs using aperture coupling. The proposed antenna has a −10 dB impedance bandwidth of 9.52% (6.0–6.6 GHz) with isolation more than 40 dB among the two ports. Realization of gain enhancement and high isolation are accomplished by simultaneously exciting two DR elements using a pair of wideband Wilkinson's power divider placed on the bottom side of the substrate. The measured gain of the proposed antenna for both the ports is found to be 12.5 dB with a front to back ratio of 16 dB. The antenna has an overall radiation efficiency of 94% and symmetrical radiation patterns with co-polarization levels 40 dB higher than the cross-polarization in both the principal planes (XY and XZ) of bore-sight direction.

Differential Dual-Band Dual-Polarized Dielectric Resonator Antenna

This communication presents a differential dual-band dual-polarized dielectric resonator antenna (DRA) with high isolation and low cross polarization using a cross-shaped DR. In the differential DRA, some of the higher order modes are eliminated and electromagnetic fields of each excited mode have no interaction with its corresponding orthogonal mode. Two groups of modes are utilized to realize dual-band characteristic and each group with two orthogonal modes is used to supply dual-polarized function. Differential feeding provides the DRA with suppression of unwanted modes, much higher isolation and lower cross-polarization in both frequency bands, compared with the traditional single-end feeding. The experimental prototypes of the proposed differential DRA and its single-ended counterpart are designed and implemented. The comparison between them is also made in reflection coefficient, isolation, and radiation properties. Both simulated and measured results show significantly improved performance of the proposed differential DRA.

Gain enhancement of a dual-polarized dielectric resonator antenna using polarization independent FSS

A dual-polarized dielectric resonator antenna (DRA) fed by two orthogonal microstrip lines has been explored employing coupled-resonator spatial filter (CRSF) frequency selective surface (FSS) as superstrate which, to the best of our knowledge, is reported for the first time. The DRA with er = 20 has been used as a primary radiator, excites fundamental TE111 mode. A CRSF FSS has been placed above the ground plane at a distance of half wavelength and a 3.4 dBi increased gain has been found compared to the gain without FSS. Using Arlon AD270 both the antenna and the FSS have been fabricated and experimental measurements have been carried out. The proposed antenna with FSS offers an impedance bandwidth of 5.1% covering frequency from 6.4 to 6.74 GHz with a maximum gain of 8.9 dBi at the resonant frequency for the port1. For the port2, the DRA with FSS resonates at 6.54 GHz with an impedance bandwidth of 5.3% covering frequency from 6.37 to 6.72 GHz. A good agreement has been observed between the measured and simulated results. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1415–1420, 2016

Pattern-Reconfigurable Dual-Polarized Dielectric Resonator Antenna

We present a portable pattern-reconfigurable dual-polarized dielectric resonator antenna (DRA). Low-cost gallium arsenide (GaAs) single-pole, double-throw (SPDT) switches are utilized to select one of the feedline paths of the DRA, giving a boresight or cardioid pattern electronically. The measured results verify the proposed antenna switches its radiation patterns between cardioid and boresight shape, without significantly affecting its matching in the operating frequency range of 5-6 GHz. Results also confirm that the pattern configuration in one port with one polarization does not affect the RF characteristics of the other port with alternative polarization of the antenna. This two-port configuration makes the proposed antenna a suitable candidate for IEEE 802.11ac multi-user multiple-input-multiple-output (MU-MIMO) applications.

Compact CPW-Fed Dielectric Resonator Antenna With Dual Polarization

A compact dual-polarized dielectric resonator antenna (DRA) fed by a coplanar waveguide (CPW) is presented. By adopting the even and odd modes of a CPW structure, two orthogonal polarizations with good isolation can be excited in the rectangular DRA by a single feeding aperture. The measured 10-dB impedance bandwidths of the two polarizations are 260 (7%) and 440 MHz (11.6%), respectively. Over the operating bandwidth, the measured isolation between two ports is better than 25 dB. A prototype was fabricated and tested. Good agreement between the measured and simulated results is obtained.

DUAL-POLARIZED DIELECTRIC RESONATOR ANTENNA WITH HIGH ISOLATION USING HYBRID FEEDING MECHANISM FOR WLAN APPLICATIONS

A dual-feed dual-polarized dielectric resonator antenna (DRA) with high isolation is proposed in this paper. The high isolation is achieved by using two hybrid feeding mechanism: one port having an H-shaped aperture coupled feed and the other with two out-of- phase probe feeds. The antenna is designed to operate at around 5.2GHz for WLAN (Wireless Local Area Network) applications and experimental results show that it has more than 35dB isolation over the entire impedance bandwidth. Good symmetric broadside radiation patterns with low cross polarizations are observed in the two principal planes, and in addition, the front-to-back (F/B) ratios for Port 1 and Port 2 are 10 and 18dB, respectively.

Dual-polarized dielectric resonator antennas

Two high input-isolation dual-polarized dielectric resonator (DR) antennas are presented in this communication. First, a slot-coupled feed technique with two narrow slots forming a T configuration is employed to design a dual-polarized DR antenna. Input isolation exceeding 35 dB has been obtained in the band for this design. Secondly, a hybrid feed mechanism with a coplanar waveguide (CPW) feed and a slot feed is used to achieve a dual-polarized DR antenna. A vertical strip is added at the center strip of the CPW feed to improve the coupling to the DR antenna. Also, input isolation exceeding 35 dB has been obtained in the band. Good cross-polarization levels less than -20 dB in the broadside direction are attained. The measured far-field radiation patterns are stable in the passband and the measured gains are around 5.5 dBi for the two feed ports of both cases.