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Electromagnetic Antennas for HF, VHF, and UHF Band Applications

Editors

Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
Interests: electromagnetic field analysis and antenna design; design of waveguide slot array; scattering from grooved/slotted conducting wedges; broadband and circularly polarized antennas
Special Issues, Collections and Topics in MDPI journals
Dept. of Electrical and Information Engineering, Seoul National University of Science and Technology, Seoul, Korea
Interests: electromagnetics and antennas

Topical Collection Information

Dear Colleagues,

Since the emerging of 4/5G, substantial effort has been devoted to microwave and millimeter-wave frequency range for electromagnetic antenna research. Nevertheless, the importance of antennas in HF, VHF, and UHF bands should not be overlooked as they are the main apparatus in most of the military, government, and industrial wireless communication systems.

MDPI Applied Sciences is announcing a Special Issue on "Electromagnetic Antennas for HF, VHF, and UHF Band Applications”. The Special Issue will explore new technologies and designs of antennas operating on HF, VHF, and UHF bands. You are cordially invited to submit a contribution to this Special Issue, of either original research or a review article. Topics include, but are not limited to, the following keywords.

Prof. Dr. Keum Cheol Hwang
Prof. Dr. Jae-Young Chung
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the collection website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Antenna design and optimization
  • Antenna measurement
  • Antenna arrays
  • Miniaturized HF, VHF, UHF antenna
  • Military antenna
  • Broadcasting antenna
  • RFID, NFC, WPT antenna
  • Radio propagation

Published Papers (16 papers)

2023

Jump to: 2022, 2021, 2020

19 pages, 3225 KiB  
Article
A 3-D Metal-Printed Dual-Polarized Ridged Waveguide Slot Array Antenna for X-Band Applications
Appl. Sci. 2023, 13(8), 4996; https://doi.org/10.3390/app13084996 - 16 Apr 2023
Cited by 1 | Viewed by 1862
Abstract
A compact three-dimensional (3-D) metal-printed ridged waveguide slot array antenna with wideband, dual linear polarization and low cross-polarization is presented for X-band applications. The proposed design achieves a compact structure due to the method of using a ridged waveguide (RWG). A vertically linear [...] Read more.
A compact three-dimensional (3-D) metal-printed ridged waveguide slot array antenna with wideband, dual linear polarization and low cross-polarization is presented for X-band applications. The proposed design achieves a compact structure due to the method of using a ridged waveguide (RWG). A vertically linear polarized (VP) array is realized through eight longitudinal shunt slots etched on the non-ridged broad wall of the RWG, while a horizontally linear polarized (HP) array is realized through eight V-shaped slots cut on the ridged broad wall of the RWG. To extend the operating bandwidth, each 1 × 8-element linear array is separated into two 1 × 4-element sub-arrays through a central feeding technique. The two sub-arrays of the VP array are excited with equal amplitude and are 180° out-of-phase through a T-junction power divider, which connects the coaxial feed and the radiated waveguide, while the two HP subarrays are directly excited by a coaxial feed with equal amplitude and remain in phase. The feed structure uses coaxial probes directly attached to the RWG to provide good mechanical stability and low voltage around the feed. An optimized 2 × 8-element dual-polarized array is fabricated using 3-D metal-printing technology for experimental verification. The measured −10 dB impedance bandwidth of the VP array is 1.2 GHz (12.2%) and, of the HP array, is 1.1 GHz (11.2%) with maximum gains of 14.6 and 15.5 dBi, respectively. There is good polarization purity over the entire operating bandwidth with a cross-polarization level better than −40 dB in the main beam direction. The isolation between two orthogonal polarized arrays is greater than 40 dB over the whole band. Full article
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13 pages, 4082 KiB  
Communication
Design of an S/X-Band Single-Layer Shared-Aperture Array Antenna Using a Mutual Complementary Configuration
Appl. Sci. 2023, 13(7), 4379; https://doi.org/10.3390/app13074379 - 30 Mar 2023
Viewed by 1233
Abstract
This paper proposes an S/X-band single-layer shared-aperture array antenna for the multifunction radars of military ships. A unit cell of the proposed antenna consists of one S-band element and four X-band elements. The S- and X-band elements are printed on the same layer [...] Read more.
This paper proposes an S/X-band single-layer shared-aperture array antenna for the multifunction radars of military ships. A unit cell of the proposed antenna consists of one S-band element and four X-band elements. The S- and X-band elements are printed on the same layer to prevent a blockage effect by upper elements in the stacked shared-aperture antenna. Herein, the S-band element has a mutual complementary configuration for the X-band elements. In addition, the unit cell of the proposed antenna is designed in a symmetrical structure, which can be flexibly extended to a full array configuration. To verify the antenna feasibility, antenna performances are measured in a full anechoic chamber. The fractional bandwidths of the S- and X-band elements are 13.6% and 13.4%, respectively. Moreover, in the 2 × 2 array configuration, the S-band array gain in the bore-sight direction varies from 5.4 dBi to 3.5 dBi when the main beam is steered from 0° to 45°. Under the same conditions, the measured X-band array gain in the bore-sight direction decreases from 13.4 dBi to 11.6 dBi. Full article
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14 pages, 5634 KiB  
Article
Conductive Ink Printed Fabric Antenna with Aperture Feeding Technique
Appl. Sci. 2023, 13(5), 2902; https://doi.org/10.3390/app13052902 - 24 Feb 2023
Viewed by 1480
Abstract
Screen-printed and inkjet-printed conductive fabric antennas have been investigated in this manuscript. The former showed optimal radiation performance after fabrication and measurement, which was the basis for developing a new fabric antenna feeding technique. The aperture-fed technique is achieved with a single coaxial [...] Read more.
Screen-printed and inkjet-printed conductive fabric antennas have been investigated in this manuscript. The former showed optimal radiation performance after fabrication and measurement, which was the basis for developing a new fabric antenna feeding technique. The aperture-fed technique is achieved with a single coaxial cable overlayed on a cut-out slot on the ground layer of the patch antenna. The cable is connected with conductive silver-based epoxy paste with high resilience to mechanical stress. Two antenna models for Bluetooth low energy (BLE) and long-range (LoRa) wireless applications were designed, fabricated, and measured at 2.44 GHz and 868 MHz, respectively, with good impedance and radiation performance. The measured antennas operated from 2.4 to 2.48 GHz (BLE) and 853 to 886 MHz (LoRa) at −10 dB S11. Measured results also showed a 56% radiation efficiency at BLE and 44.9% at LoRa. The screen-printing procedure and feeding technique have been presented in this manuscript. Full article
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2022

Jump to: 2023, 2021, 2020

11 pages, 16754 KiB  
Article
Effects of Closed-Loop Devices on Omnidirectional Beam Patterns Radiated from WAVE Monopole Antennas
Appl. Sci. 2022, 12(22), 11402; https://doi.org/10.3390/app122211402 - 10 Nov 2022
Viewed by 1071
Abstract
This study investigates the influence of closed-loop devices on omnidirectional beam patterns radiated from a Wireless Access for Vehicle Environment (WAVE) monopole antenna for facilitating communication stability in Vehicle-to-Vehicle and Vehicle-to-Everything technology. Single, dual, and quadruple closed-loop devices were introduced into the monopole [...] Read more.
This study investigates the influence of closed-loop devices on omnidirectional beam patterns radiated from a Wireless Access for Vehicle Environment (WAVE) monopole antenna for facilitating communication stability in Vehicle-to-Vehicle and Vehicle-to-Everything technology. Single, dual, and quadruple closed-loop devices were introduced into the monopole antenna, and their surface current density and radiation beam patterns were analyzed by using the high-frequency structure simulator (HFSS) and computer simulation technology (CST) programs. As the closed-loop devices reflected the signal radiated from the antenna, the distribution of the surface current was concentrated around the monopole due to the creation of a closed-loop surface current path, which increased the gain value. The average gain was considerably increased by introducing closed-loop devices. The proposed antenna has an average gain of 1.57 dBi and a peak gain of 6.29 dBi at the operating frequency. Furthermore, omnidirectional beam patterns with a beam width of 359° were obtained by introducing four closed-loop devices into the monopole antenna, which eliminated nearly all null points in the frequency range of 5.85–5.925 GHz. Full article
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10 pages, 4092 KiB  
Article
A VHF Band Small CRLH Antenna Using Double-Sided Meander Lines
Appl. Sci. 2022, 12(20), 10676; https://doi.org/10.3390/app122010676 - 21 Oct 2022
Viewed by 1109
Abstract
In this paper, a miniaturized very-high frequency (VHF) band antenna using both top and bottom meander lines is proposed. To design a compact size antenna in the VHF band, a Composite Right/Left-Handed (CRLH) transmission line is applied to antenna structure; additionally, both top [...] Read more.
In this paper, a miniaturized very-high frequency (VHF) band antenna using both top and bottom meander lines is proposed. To design a compact size antenna in the VHF band, a Composite Right/Left-Handed (CRLH) transmission line is applied to antenna structure; additionally, both top and bottom meander lines were used to achieve a greater inductance. The CRLH transmission line unit cell operates at 88 MHz, and the fabricated antenna is designed by arranging 7-unit cells. The overall size of the proposed antenna is 0.087λ × 0.02λ × 0.0003λ at the lowest operating frequency, and the antenna operates at 84 MHz. The VSWR 3.5:1 reference operating bandwidth of the antenna is 2%. The received power of the proposed CRLH antenna was measured to verify the antenna performance. Full article
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14 pages, 4954 KiB  
Article
Effect of Buildings on the Radiation Characteristics of MF Broadcast Antennas
Appl. Sci. 2022, 12(13), 6525; https://doi.org/10.3390/app12136525 - 27 Jun 2022
Cited by 1 | Viewed by 1376
Abstract
This study aims to investigate the impact of the presence of buildings on the radiation characteristics of MF broadcast antennas. Two different antennas are considered: a monopole operating at 1494 kHz and a two-element linear array radiating at 1008 kHz. The buildings were [...] Read more.
This study aims to investigate the impact of the presence of buildings on the radiation characteristics of MF broadcast antennas. Two different antennas are considered: a monopole operating at 1494 kHz and a two-element linear array radiating at 1008 kHz. The buildings were modeled as wire-grids and the total electric field intensity was calculated as the sum of the scattered field by the wire-grid and the field radiated from the antenna in free space. The radiation pattern of the antennas, when one or two buildings were situated in their vicinity, were the end result of the analysis, and they were compared to the corresponding patterns in free space. The results demonstrate that the radiation characteristics of antennas are mostly affected by the heights of buildings. If these heights are less than a critical value, the buildings do not significantly obstruct the operation of the antenna, despite the value of other parameters, such as the length and the width of the buildings, as well as their distance from the antenna. Full article
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13 pages, 800 KiB  
Article
Derivation of a Universally Valid Array Factor of a Conformal Arrays Based on Phase Compensation and Genetic Learning Particle Swarm Optimization
Appl. Sci. 2022, 12(13), 6501; https://doi.org/10.3390/app12136501 - 27 Jun 2022
Cited by 2 | Viewed by 1406
Abstract
In this study, we investigated the recent deterioration of the radiation pattern performance of conformal arrays, which are applied to fields such as aircraft and vehicles. We analyzed the radiation pattern of conformal arrays in the array factor stage by combining previous studies [...] Read more.
In this study, we investigated the recent deterioration of the radiation pattern performance of conformal arrays, which are applied to fields such as aircraft and vehicles. We analyzed the radiation pattern of conformal arrays in the array factor stage by combining previous studies on various beam-forming techniques for conformal arrays. To efficiently calculate and utilize the radiation pattern of conformal arrays, we derived an array factor based on phase composition for nonplanar arrays of three-dimensional (3D) coordinate systems. As an amplitude tapering method for controlling the sidelobe level of the derived 3D array factor, we propose a Bernstein polynomial generalization method based on Genetic Learning Particle Swarm Optimization. The proposed 3D array factor was verified using a cavity-backed patch antenna operating at the X-band through EM simulation of conformal arrays as a single element. Full article
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14 pages, 1797 KiB  
Article
Assessment of Radiofrequency Exposure in the Vicinity of School Environments in Crete Island, South Greece
Appl. Sci. 2022, 12(9), 4701; https://doi.org/10.3390/app12094701 - 07 May 2022
Cited by 5 | Viewed by 1406
Abstract
This study aimed to estimate the radiofrequency exposure levels in the vicinity of nursery and primary schools at the northwest part of Crete island in Greece. Moreover, the compliance with the exposure limits, according to Greek legislation, was investigated. A total of 396 [...] Read more.
This study aimed to estimate the radiofrequency exposure levels in the vicinity of nursery and primary schools at the northwest part of Crete island in Greece. Moreover, the compliance with the exposure limits, according to Greek legislation, was investigated. A total of 396 in situ frequency-selective and broadband measurements were conducted around 69 schools, classified in urban and suburban environments, in the range of 27–3000 MHz (subdivided in seven frequency bands). The measured value of the electric field strength (V/m) was recorded and, subsequently, the exposure ratio was calculated. Statistical analysis was performed in order to analyze and evaluate the data. In addition, a worst-case scenario was examined by considering the highest measured exposure level around each school. The statistical tests indicated that the mean and median values of the exposure ratio, even in the worst-case scenario, were found well below 1 for all frequency bands. The calculated distributions of the electric field measurements demonstrated that almost 90% of the latter were below 1 V/m, with the majority of values lying in the range of 0.5–1 V/m. The main contributors to the total exposure were the mobile communication frequencies and broadcasting, while the exposure was greater in urban than in suburban environments. Full article
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9 pages, 2492 KiB  
Article
An Approach for Modelling Harnesses in the Extreme near Field for Low Frequencies
Appl. Sci. 2022, 12(6), 3202; https://doi.org/10.3390/app12063202 - 21 Mar 2022
Viewed by 1321
Abstract
A key part of every space science mission, in the system-level approach, is the detailed study and modeling of the emissions from transmission lines. Harnesses usually emit electromagnetic fields due to the currents (of common and/or differential modes) that flow on their shields. [...] Read more.
A key part of every space science mission, in the system-level approach, is the detailed study and modeling of the emissions from transmission lines. Harnesses usually emit electromagnetic fields due to the currents (of common and/or differential modes) that flow on their shields. These fields can be identified via conducted emissions measurements. Relying on the operating frequency, any cable can be considered as a dipole or a traveling-wave antenna. Limited work can be found in the literature regarding modeling methodologies for cable topologies, especially in the low frequency (ELF, SLF, VLF, LF) domain. This work intends to provide perceptions for the precise estimation of harness radiated emissions, consider a mission-specific measurement point (where the sensors are placed), and follow ESA’s recent science mission studies for electromagnetic cleanliness applications. For the low frequencies considered herein, any linear cable path is considered as a point source (infinitesimal dipole) and we evaluate its effect on the calculated electric field extremely close to the source. For such distances, it is shown that the dipole representation is not accurate. To remedy this phenomenon, this article proposes a methodology, which can be easily expanded to complex cable geometry cases. Full article
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2021

Jump to: 2023, 2022, 2020

14 pages, 703 KiB  
Article
Compact and High Gain 4 × 4 Circularly Polarized Microstrip Patch Antenna Array for Next Generation Small Satellite
Appl. Sci. 2021, 11(19), 8869; https://doi.org/10.3390/app11198869 - 23 Sep 2021
Cited by 8 | Viewed by 5371
Abstract
In this article, a high gain and compact 4 × 4 circularly polarized microstrip patch antenna array is reported for the data transmission of the next-generation small satellite. The radiating element of the circularly polarized antenna array is realized by the conventional model [...] Read more.
In this article, a high gain and compact 4 × 4 circularly polarized microstrip patch antenna array is reported for the data transmission of the next-generation small satellite. The radiating element of the circularly polarized antenna array is realized by the conventional model of the patch with truncated corners. A compact two-stage sequential rotational phase feeding is adopted that broadens the operating bandwidth of the 4 × 4 array. A small stub is embedded in the sequential rotational feed, which results in better performance in terms of the S-parameters and sequential phases at the output ports than sequential rotational feed without open stub. A prototype of the array is fabricated and measured. Fulfilling the application requirements of the next-generation small satellites, the array has the left-handed circularly polarized gain of more than 12 dBic with the axial ratio level below 1.5 dB in the ±10 angular space with respect to the broadside direction for the whole bandwidth from 8.05 GHz to 8.25 GHz. Moreover, the left-handed circularly polarized gain varies from 15 to 15.5 dBic in the desired band. The radiation patterns are measured; both the co- and X-pol are validated. Full article
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2020

Jump to: 2023, 2022, 2021

9 pages, 3081 KiB  
Article
Double-Dielectric Microstrip Ultrahigh-Frequency Antenna for Digital Terrestrial Television
Appl. Sci. 2020, 10(23), 8640; https://doi.org/10.3390/app10238640 - 03 Dec 2020
Cited by 5 | Viewed by 2219
Abstract
In many countries, terrestrial broadcasting is the main delivery medium for television. In this paper, we propose a small-volume practical receiving antenna. Our design consists of a linear array of three vertically placed patch antennas which increase antenna gain. The antenna has a [...] Read more.
In many countries, terrestrial broadcasting is the main delivery medium for television. In this paper, we propose a small-volume practical receiving antenna. Our design consists of a linear array of three vertically placed patch antennas which increase antenna gain. The antenna has a double-dielectric substrate (FR4 + air) in order to increase efficiency and bandwidth. In this paper, we also discuss simulations and practical results, and demonstrate that the proposed double-dielectric microstrip antenna is a viable design choice for digital terrestrial TV (DTT) reception. The designed antenna reached a gain of 10.5 dBi at the desired central frequency of 754 MHz. Full article
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15 pages, 6630 KiB  
Article
Design and Characterization of VHF Band Small Antenna Using CRLH Transmission Line and Non-Foster Matching Circuit
Appl. Sci. 2020, 10(18), 6366; https://doi.org/10.3390/app10186366 - 12 Sep 2020
Cited by 4 | Viewed by 3432
Abstract
In this paper, we propose an electrically small antenna consisting of a composite right/left-handed (CRLH) transmission line (TL) and a non-Foster matching circuit. An interdigital capacitor (IDC) and spiral inductor are used to fabricate the very high frequency (VHF) band antenna based on [...] Read more.
In this paper, we propose an electrically small antenna consisting of a composite right/left-handed (CRLH) transmission line (TL) and a non-Foster matching circuit. An interdigital capacitor (IDC) and spiral inductor are used to fabricate the very high frequency (VHF) band antenna based on CRLH TL. The size of the proposed antenna is as small as 0.025 × 0.014 × 0.0008 λ at 145.5 MHz using the zeroth-order resonant generated by the CRLH TL. The antenna operation bandwidth is extended by the non-Foster circuit (NFC) consisting of a pair of transistors in a cross-coupled manner. An antenna prototype is fabricated and the input impedance, the received power, and gain of the proposed antenna are measured. The results show that the broadband characteristic is maintained while the form factor is extremely small compared to the wavelength. The average received power enhancement and increased bandwidth of antenna are 17.3 dB and 335.5 MHz (from 249.2–268.2 to 145.5–500 MHz), respectively. The calculated gain of the proposed antenna with the non-Foster is about −45 dBi at 155 MHz. The proposed antenna can be considered as a potential candidate of a low-profile antenna for military ground communications at the VHF band. Full article
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9 pages, 2752 KiB  
Article
SNR Enhancement of an Electrically Small Antenna Using a Non-Foster Matching Circuit
Appl. Sci. 2020, 10(13), 4464; https://doi.org/10.3390/app10134464 - 28 Jun 2020
Cited by 1 | Viewed by 3757
Abstract
A non-Foster circuit (NFC) is known as an active broadband matching technique to improve the impedance matching bandwidth of an electrically small antenna (ESA). There has been a vast amount of papers that report the generation of negative impedance using an NFC and [...] Read more.
A non-Foster circuit (NFC) is known as an active broadband matching technique to improve the impedance matching bandwidth of an electrically small antenna (ESA). There has been a vast amount of papers that report the generation of negative impedance using an NFC and its effectiveness on broadband antenna matching. However, only a few discussed its impact on the signal-to-noise-ratio (SNR), which is one of the most important figures-of-merit for a wireless communication system. In this paper, the SNR enhancement due to an NFC was measured and discussed. An NFC was carefully designed to have a low dissipation loss and to meet the stability conditions. The optimized NFC design was fabricated and applied to an ESA length of λ⁄15 at a frequency range of 150 to 300 MHz. The measured results showed that the NFC enhanced the received power of the antenna system by more than 17 dB. However, due to the noise added by the NFC, the SNR enhancement was not guaranteed for some frequency points. Nevertheless, an average of 7.3 dB of SNR improvement over the frequency band of interest is possible based on the experiment result. Full article
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11 pages, 2012 KiB  
Article
Design of Dual Circularly Polarized Sequentially-Fed Patch Antennas for Satellite Applications
Appl. Sci. 2020, 10(6), 2107; https://doi.org/10.3390/app10062107 - 20 Mar 2020
Cited by 7 | Viewed by 3709
Abstract
In this paper, we present the design and fabrication of two dual circularly polarized (CP) patch antennas that can be profitably used as feeders for reflector systems normally adopted for satellite applications. In the first part of the manuscript, we propose the optimization [...] Read more.
In this paper, we present the design and fabrication of two dual circularly polarized (CP) patch antennas that can be profitably used as feeders for reflector systems normally adopted for satellite applications. In the first part of the manuscript, we propose the optimization of a dual-CP patch antenna, loaded by a fence of passive monopoles around it to increase antenna gain for high elevation angles. To achieve dual-CP operation mode, the circular patch has been sequentially-fed by three pins, whose mutual phase-shift is equal to 120 . The antenna feeding network was placed on the antenna back and designed using microstrip technology. Two different input ports provide both right-hand (RH) and left-hand (LH) circular polarizations. A prototype of such an antenna was fabricated and measured at f = 8 . 25 GHz. Furthermore, to test the versatility of the proposed single radiating patch, in the second part of the manuscript, we present the results of geometrically scaling at f = 2 . 2 GHz (higher UHF band) and this was used as a building block for the design of a dual-CP sequentially-fed 2-by-2 array antenna. The results for both the proposed antennas are satisfactory in terms of impedance bandwidth, broad radiation pattern, gain and cross-polarization rejection, thus they can be profitably used as feeders for reflectors at relatively low frequencies. Full article
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9 pages, 2966 KiB  
Article
Design and Performance Prediction of a Dual-Band Coupled-Fed Dipole Array Antenna for PCL Systems in the VHF Band
Appl. Sci. 2020, 10(5), 1835; https://doi.org/10.3390/app10051835 - 06 Mar 2020
Cited by 2 | Viewed by 2694
Abstract
This article proposes the design of a dual-band coupled-fed dipole antenna for passive coherent location (PCL) systems in the very high frequency (VHF) band. The proposed indirect coupled feed mechanism, which is often employed in microstrip patch antennas, is first applied to VHF [...] Read more.
This article proposes the design of a dual-band coupled-fed dipole antenna for passive coherent location (PCL) systems in the very high frequency (VHF) band. The proposed indirect coupled feed mechanism, which is often employed in microstrip patch antennas, is first applied to VHF band dipole elements for dual-band matching. To confirm the effectiveness of the proposed design, we fabricate the coupled-fed dipole element and measure antenna characteristics, such as the voltage standing wave ratio (VSWR) and the antenna gain. The proposed antenna element is then applied to an eight-element circular array to form the reference and surveillance beams for PCL systems. Finally, the target location is estimated by constructing amplitude-range doppler (ARD) maps for one frequency modulation (FM) and two terrain digital multimedia broadcasting (T-DMB) illuminators in the Seoul-Gyunggi urban area. The results confirm that the proposed element is suitable for dual-band PCL systems in the VHF band compared to a conventional dipole antenna. Full article
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10 pages, 4697 KiB  
Article
Wideband UHF Antenna for Partial Discharge Detection
Appl. Sci. 2020, 10(5), 1698; https://doi.org/10.3390/app10051698 - 02 Mar 2020
Cited by 11 | Viewed by 3078
Abstract
This paper presents a ultra-high frequency (UHF) antenna for partial discharge (PD) detection and the antenna sensor can be used near a conducting ground wire. The proposed UHF antenna has advantages of easy setup and higher-frequency detection over the high-frequency current transformer (HFCT) [...] Read more.
This paper presents a ultra-high frequency (UHF) antenna for partial discharge (PD) detection and the antenna sensor can be used near a conducting ground wire. The proposed UHF antenna has advantages of easy setup and higher-frequency detection over the high-frequency current transformer (HFCT) sensor. First, a variety of loop-shaped antennas are designed to compare each near field coupling capability. Then, a new UHF antenna is designed based on the loop-shaped antenna, which has the best near field coupling capability. Finally, the proposed UHF antenna is fabricated and measured. It provides a wide impedance bandwidth of 760 MHz (740–1500 MHz). Its simple setup configuration and wide bandwidth frequency response in the UHF band can provide a more efficient means for PD detection. Full article
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