End-fire Antenna Research Articles

A Millimeter-Wave Dual-Polarized Endfire Antenna With Ultrawideband and High Isolation for 5G Multibeam Systems

A Millimeter-Wave Dual-Polarized Endfire Antenna With Ultrawideband and High Isolation for 5G Multibeam Systems

A novel ultra-wideband end-fire antenna based on spoof surface plasma polaritons

Abstract A novel ultra-wideband end-shot antenna based on artificial surface-isolated excitations (SSPP) is designed. The antenna adopts a coplanar waveguide structure and introduces an SSPP transmission line consisting of a symmetric exponential Gaussian curve reference ground and an elliptical aperture-type cell, which effectively improves the bandwidth of the SSPP antenna and realizes the high-frequency operating characteristics of this antenna. In addition, the design combines the asymmetric structure of the SSPP transmission line and the guided branch structure to enhance the directivity of the antenna. The measured results of the antenna show that the antenna operates in the bandwidth range of 21.5–34.0 GHz, and the average gain of the antenna in the whole operating bandwidth range reaches 9.4 dBi, and the average radiation efficiency is 92.6 %, which can be better applied in the field of high-frequency communication.

Miniaturized low-profile end-fire antenna based on spoof surface plasmon polaritons

Miniaturized low-profile end-fire antenna based on spoof surface plasmon polaritons

Design and Modelling of a Modified High Gain Printed Vivaldi Antenna for EMC Measurements

This paper demonstrates the design, modeling, and analysis of a small size 180 × 165 × 1.6 mm3 printed broadband Vivaldi antenna for electromagnetic compatibility measurements. The proposed antenna is intended to be utilized as a reference antenna for emission and immunity tests inside the EMC Chamber through the band (0.8–5.5 GHz). Exponentially tapered slots were created based on mathematical equations to form an end-fire radiation antenna. Furthermore, microstrip and slot line stubs were employed to tune the impedance bandwidth. This antenna could be considered a 2-D Horn antenna with a size reduction of 64% and 67% since both antennas, Vivaldi and Horn are based on the same principle. Two rectangular slots were engraved near the feeding point to reshape and enhance the gain at lower frequency bands. Furthermore, the realized gain has been improved by approximately 3.5 dB and reached up to 10.7 dBi by introducing a pair of triangular reversal slots at the top edges of the structure. Moreover, this antenna has specifications that make it a suitable candidate to work as a reference antenna inside the EMC chamber compared to the classical Horn antenna offered for sale (PowerLOG® PRO 30800 and TBMA4).

Low-profile, low sidelobe array antenna with ultrawide beam coverage for UAV communication

This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage, low profile, and low Sidelobe Level (SLL) for the application of Unmanned Aerial Vehicle (UAV) air-to-ground communication. The array consists of ten broadside-radiating, ultrawide-beamwidth elements that are cascaded by a central-symmetry series-fed network with tapered currents following Dolph-Chebyshev distribution to provide low SLL. First, an innovative design of end-fire Huygens source antenna that is compatible with metal ground is presented. A low-profile, half-mode Microstrip Patch Antenna (MPA) is utilized to serve as the magnetic dipole and a monopole is utilized to serves as the electric dipole, constructing the compact, end-fire, grounded Huygens source antenna. Then, two opposite-oriented end-fire Huygens source antennas are seamlessly integrated into a single antenna element in the form of monopole-loaded MPA to accomplish the ultrawide, broadside-radiating beam. Particular consideration has been applied into the design of series-fed network as well as antenna element to compensate the adverse coupling effects between elements on the radiation performance. Experiment indicates an ultrawide Half-Power Beamwidth (HPBW) of 161° and a low SLL of −25 dB with a high gain of 12 dBi under a single-layer configuration. The concurrent ultrawide beamwidth and low SLL make it particularly attractive for applications of UAV air-to-ground communication.

An X-band beam-scanning reflectarray antenna stimulated using a spoof surface plasmon polaritons based low profile endfire MIMO antenna

A single-layer, low-profile beam scanning reflectarray (RA) fed by a spoof surface plasmon polaritons (SSPPs) based endfire MIMO antenna is proposed in this manuscript. The RA is based on a variable elliptical-shaped unit cell designed at 10.4 GHz. The unit cell has a low insertion loss of 2.3 dB and a reflection phase of 315.2°in the working frequency band from 9.52–11.23 GHz. The SSPPs based endfire MIMO antenna is used to mitigate the aperture blockage, achieve high isolation between the feed elements, and accomplish the continuous one-dimensional (1-D) beam scanning of ± 8°from the broadside. The maximum realized gain of the proposed reflectarray in the broadside direction is 22.6 dBi with a 3-dB beamwidth of 5.7°. The minimal beam switching loss is in the other direction, and the realized gain is 22.4 dBi with a 3-dB beamwidth of 5.8°. The 3-dB gain bandwidth (GBW) of 9.7 % of the proposed RA benefits nano-satellite applications. The fabricated prototype measurements in an anechoic chamber environment verify the simulated results.

Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

A low profile, vertically polarized, ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency (UHF) band is developed in this paper. The array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array height. Capacitance is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse dimension. Simulated results show that when the antenna array operates in a frequency range of 300 MHz–900 ​MHz, the end-fire radiation pattern achieves ±45° scanning range in the horizontal plane. Then prototypes of the proposed end-fire antenna element and a uniformly spaced linear array (1×2) are fabricated and validated. The end-fire antenna array should be suitable for airborne applications where low profile and conformal scanning phased antenna arrays with end-fire radiations are required. This design is attractive for airborne platform applications that are used to search, discover, identify, and scout the aerial target with vertically polarized beams.

A compact wideband antenna with high gain based on spoof surface plasmon polaritons

In this paper, a novel wideband antenna with a simple structure and low profile based on spoof surface plasmon polaritons (SSPPs) is proposed. The structure consists of periodically modulated corrugated metal strips as transmission lines, a CPW feed, and a ground metal plate as an antenna reflector. The SSPP transmission line is used to convert quasi-TEM to SSPP mode and achieve optimal impedance matching. The prototype of the end-fire antenna has been designed and fabricated. The simulation results show that this antenna can achieve a gain of 10.19 dB, a bandwidth of 146%, and an efficiency of 90% in a wide operating band from 7 to 45 GHz. The proposed design illustrates great potential that includes high efficiency, good directivity, high gain, wide bandwidth, and easy manufacturing.

A low-profile high-isolation endfire MIMO antenna based on spoof surface plasmon polaritons for X-band applications

This work proposes a three-port, low-profile, coplanar endfire multiple-input-multiple-output (MIMO) antenna based on spoof surface plasmon polaritons (SSPPs). The proposed antenna comprises a coplanar waveguide (CPW)-fed SSPPs transmission line (TL). A transition to transform the CPW quasi-TEM mode to the SSPPs mode. The radiator section with asymmetric discontinuities converts the bounded SSPPs waves into radiating waves. The proposed MIMO antenna exploits the inherent feature of high isolation in the SSPPs TL due to its strong field confinement competency. Wider beamwidths for ample azimuth and elevation coverage with a stable pattern in the endfire direction are achieved in the 9.52–11.23 GHz operating band. In the operating band, the MIMO antenna has an average realized gain of 6 dBi. Mainly, it has high isolation below -35 dB (measured) in the operating range, a maximum envelope correlation coefficient (ECC) of 1.5 × 10−3, and a total active reflection coefficient (TARC) value below 0.3. The measured results are closely matched with the simulated ones in terms of S-parameters, radiation pattern, ECC, TARC, and CCL.

High gain antipodal meander line antenna for point-to-point WLAN/WiMAX applications

This paper introduces a planar antipodal meander line antenna fabricated using RO3003 substrate. The proposed antenna is designed to radiate in the end-fire direction, achieving a maximum measured gain of 10.43 dBi within its working bandwidth, which ranges from 2.24 GHz to 2.7 GHz, covering long-range WLAN/WiMAX applications. A systematic procedure is adopted in the design process to prove its tunability to cover other application requirements in terms of gain and bandwidth. The proposed design steps show that the bandwidth and the gain can independently be controlled by adjusting specific design parameters such as the number of radiators and the scaling factor. The antenna is fine-tuned using sensitivity analysis and parametric study to guarantee optimum operation at the desired bandwidth. Experimental measurements of the fabricated design demonstrate a high degree of correlation with simulations conducted using CST and HFSS. In comparison to other end-fire antennas presented in the literature, the proposed design manifests its capability to provide high gain for WLAN/WiMAX nodes connectivity. The measurements show that the proposed traveling wave antenna exhibits a high radiation efficiency with maximum value of 99.8% at 2.35 GHz. The measured side lobe level is found to be below -18\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-18$$\\end{document} dB and -20\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-20$$\\end{document} dB at 2.45 GHz along the E\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E$$\\end{document}- and H\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$H$$\\end{document}-planes, respectively. Apart from its excellent radiation performance, the antenna is characterized by its low profile and fabrication simplicity.

Wideband Wide-Angle Scanning Endfire Phased Array Antenna Based on Heterogeneous Beam Elements for Millimeter-Wave Mobile Terminals

Wideband Wide-Angle Scanning Endfire Phased Array Antenna Based on Heterogeneous Beam Elements for Millimeter-Wave Mobile Terminals

An Endfire Leaky Wave Antenna With Flexible Modification on the Phase and Attenuation Constants

An Endfire Leaky Wave Antenna With Flexible Modification on the Phase and Attenuation Constants

Design of a novel wide-angle Rotman lens beamformer for 5G mmWave applications

The attachment of 5G with millimeter wave (mmWave) frequencies offers massive capacity and low latency to reveal the full 5G experiences. High directive gain and beamforming are considered essential for mmWave 5G systems. The main requirements of the beamforming network for 5G mmWave applications are the scanning coverage of ± 60° and SLL > 10 dB in a wide operational bandwidth over the standard 5G frequency bands. In this paper, a novel PCB-based wide-angle Rotman lens beamformer is designed, simulated, and successfully measured to meet the mentioned requirements for 5G mmWave applications. A comprehensive improved design methodology is provided for all components of the Rotman lens to reach a wide scanning angle, enhanced sidelobe level, and low scan loss. The end-fire Vivaldi antenna is selected as an array element for easy integration to the beamforming network as well as its capability to use in dual-polarization configuration. The proposed Rotman lens is operational in the 24–30 GHz frequency band covering 5G n257, n258, and n261 frequency bands. The results show a nearly constant 8 beams across the whole bandwidth steering from − 53° to 53° in 15° increments to provide ± 60° coverage with the SLL > 10 dB and scan loss < 1.9 dB. The retrieved novelties from this work contain an effective design methodology for an optimized Rotman lens with wide-scan angle and low phase and amplitude error, non-uniform distribution based array ports, and integration with end-fire antenna for possible dual polarization and 2-D beamforming capabilities. The comparison of the proposed beamformer with the most recent works shows several advantages in terms of integrated structure and performances including bandwidth, wide scanning angle, SLL, and scan loss. With such performances, this beamformer can be used for various mmWave and 5G applications such as advanced antenna systems, massive MIMO systems, and hybrid beamforming systems.

Millimeter-wave End-Fire Magneto-Electric Dipole Antenna and Array with Horizontal Polarization and Wide Bandwidth

Millimeter-wave End-Fire Magneto-Electric Dipole Antenna and Array with Horizontal Polarization and Wide Bandwidth

Frequency Reconfigurable Endfire Antenna Using Coupled-Type Hybrid Radiator with Wide Tuning Range

Frequency Reconfigurable Endfire Antenna Using Coupled-Type Hybrid Radiator with Wide Tuning Range

Single Conductor Endfire Antenna with Easy Assembly and High Gain for 5G Millimeter Wave Application

Single Conductor Endfire Antenna with Easy Assembly and High Gain for 5G Millimeter Wave Application

A Dual-polarized Endfire Antenna with Wideband and Enhanced Isolation for 5G Millimeter-wave Phased Array

A Dual-polarized Endfire Antenna with Wideband and Enhanced Isolation for 5G Millimeter-wave Phased Array

Directive Millimeter-Wave End-Fire Diplexing Antenna for IoT Applications

Millions of passengers use High-speed trains (HSTs) daily, in the world. The roofs of HSTs can be equipped with a variety of transmitting and receiving antennas to accommodate high-data-rate Internet services with reliable radio access for passengers. The design of commercial antenna systems is a compromise between cost, size, manufacturability, and performance. This paper proposes a new, compact and low-cost two-port millimeter-wave diplexing directive end-fire antenna, which is designed, fabricated and tested. The proposed antenna is made of a tapered slot antenna and a diplexing structure based on transitions in stacked Printed Circuit Boards (PCBs). The ports of the antenna cover the frequency band 25.9-32.4 GHz (6.5 GHz) and 34.6-37.1 GHz (2.5 GHz). In all operating frequency bands, measured isolation between input ports exceeds 24 dB. Furthermore, symmetric directive end-fire radiation patterns are obtained experimentally, with low side lobe level and low front-to-back ratio. All these features make the proposed diplexing antenna suitable for high-speed railway wireless networks.

A Novel Quad-Band Branched Monopole Antenna with a Filter Suppressing Higher Order Modes

This paper proposes a novel quad-band branched monopole antenna with a filter. The proposed antenna has a simple configuration in which branch-elements are added to a basic configuration consisting of a mast and dielectric wires. The antenna is characterized by performances such as wideband impedance matching, gain stabilization, and gain enhancement. Wideband impedance characteristics satisfying the voltage standing ratio of less than 2 are obtained by exciting a parallel resonance at the lowest band and multi-resonance at high bands. The filter suppressing higher order modes is used for gain stabilization, so that averaged gains above 5 dBi are obtained at the quad-band. The antenna has a high gain of 11.1 dBi because the branch-elements work as an end-fire array antenna at the highest band. Furthermore, it is clarified that an operating frequency is switched by using a variable bandpass filter at the lowest band. Last, a scale model of the antenna is fabricated and measured, then the effectiveness of the proposed antenna is demonstrated.

A Ka-Band Broadband Polyjet 3-D Printed Quasi-Planar End-Fire Antenna With Partially Hollowed Substrate and Gain Compensation

This letter presents a new class of millimeter-wave broadband quasi-planar end-fire antenna featuring flexible design and enhanced structural compatibility with additive manufacturing technology. The broadband end-fire radiation performance is enabled by a coupling-probe-fed rectangular patch that is vertically attached to the sidewall of dielectric substrate of the antenna. The patch and ground of the antenna are perpendicular to the plane of the feeding transmission line and the metal parts of the antenna are embedded into the dielectric substrate. The architecture allows excitation of vertically polarized patterns of the patch. More significantly, the dielectric substrate is hollowed selectively to improve the realized gain in the main-lobe orientation, thus enhancing stability of the radiation patterns in a wide operational bandwidth. A <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Ka</i> -band prototype of the proposed antenna is shaped into a 3-D-printing-compatible geometry and is monolithically integrated by exploiting high-precision Polyjet 3-D printing process. The manufactured antenna demonstrates good radiation patterns in a −10-dB impedance bandwidth from 28.8 to 37.0 GHz with in-band realized gains of 2.5–5.0 dBi.