Design Of Dipole Antenna Research Articles

Broadband printed dipole antenna with integrated balun and tuning element for DTV application

This paper presents the broadband printed dipole antenna design with an integrated balun and tuning element for DTV applications. The proposed technique is a unique tuning mechanism that is straddled between the gap of the proposed dipole antenna. This enables the frequency range of the dipole antenna to be adjusted to tightly cover the specified Digital TV band, thereby mitigating interference from signals outside the band that would otherwise degrade the quality of the DTV signal. The measured results confirm that the proposed antenna covers an impedance bandwidth of 414.5 MHz from 457.7 to 872.2 MHz, which covers the frequency band of DTV systems (470–862 MHz). Furthermore, the proposed antenna has excellent omnidirectional radiation with a maximum realized gain of 2.95 dBi. These results demonstrate the suitability of the antenna for DTV applications.

Ultra-Wideband Hybrid Magneto-Electric Dielectric-Resonator Dipole Antenna Fed by a Printed RGW for Millimeter-Wave Applications

Future communication standards have an increasing interest in Millimeter Wave (mm-wave) bands, where wide bandwidth and secured communication can be assured. This trend in communication standards stimulates the research community to provide novel antenna configurations in the mm-wave bands. This article proposes a novel design and analysis of hybrid magneto-electric dielectric-resonator dipole antenna that features an electrically small size with ultra-wideband operation and consistent radiation characteristics in the mm-wave band. The proposed antenna is designed based on the combination of multi-resonances produced by a Magneto-Electric (ME) dipole and stacked Dielectric Resonator Antennas (DRAs). In addition, the proposed antenna is implemented using state-of-the-art Printed Circuit Board (PCB) technology, namely, Printed Ridge Gap Waveguide (PRGW) for low loss and cost-efficiency. The combination between the ME-dipole and stacked DRA is adopted to ensure symmetric radiation characteristics in both E- and H-planes over ultra-wideband operation with a deep matching level. Both DRA and ME-dipole elements are designed and studied separately, where a systematic design procedure is presented to obtain initial design parameters. Proper integration between the radiating elements introduced an electrically small size antenna ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.64\,\,\lambda \times 0.48\lambda $ </tex-math></inline-formula> ) covers the full Ka-band (26-40 GHz) with a matching level beyond −20 dB and gain stability of 8± 1 dB. The antenna prototype is fabricated, where a good agreement is shown between both simulated and measured results.

종이접기와 키리가미 이론에 기반한 3차원 T-자형 다이폴 안테나 설계

In this study, the design of a 3D foldable T-shaped dipole antenna inspired by origami and kirigami theory is presented. The origami- and kirigami-inspired techniques map 2D to 3D space. Moreover, the lamina emergent torsional (LET) joint is designed to fold the planar structure. The proposed antenna, including the LET joint, is printed on a planar 0.5 mm thick FR4 substrate. The proposed antenna is fed by a capacitively coupled microstrip line to achieve a 20 % fractional bandwidth (2.7~3.3 GHz), with a measured antenna gain value of 6.5 dBi.

Dipole-Fed Rectangular Dielectric Resonator Antennas for Magnetic Resonance Imaging at 7 T: The Impact of Quasi-Transverse Electric Modes on Transmit Field Distribution

Shortened dipole antennas based on rectangular dielectric blocks play an important role in ultrahigh field magnetic resonance imaging (UHF-MRI) radio frequency (RF) coil design. However, the generally assumed direct contact with the subject is difficult to maintain in typical in vivo settings. We have previously observed that certain dielectrically shortened dipole antennas can produce a substantially altered transmit field distribution with a very low transmit efficiency when the block and the sample are physically separated. Therefore, the aim of this study was to determine a) why certain designs of dielectrically shortened dipole antennas can produce an inefficient transmit field when the block and the sample are physically separated and b) how this depends on key parameters such as rectangular block geometry, dielectric constant, loading geometry, and RF feeding. In this work, two main types of quasi-transverse dielectric modes were found in different rectangular block geometries and interpreted as TE11δz (MR efficient) and TE1δδy (MR inefficient), and their impact on in vivo MRI experiments involving the human head, calf, and wrist was explored. This study shows, for the first time, why certain antennas preserve their transmit field efficiency despite physical separation from the sample. We conclude that the proposed approach has the potential to provide new insights into dipole antenna design for UHF-MRI.

Wideband Triple Sleeve Dipole Antenna with Loading for UHF Applications

ABSTRACT A novel miniaturized dipole antenna design incorporating triple sleeves and shorting load leading to enhanced bandwidth is proposed in the present work. The Triple Sleeve Dipole Antenna with Shorting Loads is designed from 500 to 3000 MHz with no tuning mechanism. The concept of triple sleeve and distributed shorting loads reduced the length of the antenna by 51.5% compared to a half wave dipole antenna at the lowest frequency. The equivalent circuit of the antenna in terms of lumped elements is determined by using a Genetic algorithm. The proposed antenna is simulated in CST Microwave Studio, fabricated, evaluated and the results are presented. The antenna can be used for trans-receive applications of wireless communications in military systems.

Design of an Intraoral Dipole Antenna for Dental Applications.

In dental MRI, intraoral coils provide higher signal-to-noise ratio (SNR) than coils placed outside the mouth. This study aims to design an intraoral dipole antenna and demonstrates the feasibility of combining it with an extraoral coil. Dipole antenna design was chosen over loop design, as it is open toward the distal; therefore, it does not restrain tongue movement. The dipole design offers also an increased depth-of-sensitivity that allows for MRI of dental roots. Different dipole antenna designs were simulated using a finite-difference-time-domain approach. Ribbon, wire, and multi-wire arms were compared. The best design was improved further by covering the ends of the dipole arms with a high-permittivity material. Phantom and in vivo measurements were conducted on a 3T clinical MRI system. The best transmit efficiency and homogeneity was achieved with a multi-wire curved dipole antenna with 7 wires for each arm. With an additional high-permittivity cap the transmit field inhomogeneity was further reduced from 20% to 5% along the dipole arm. When combined with extraoral flexible surface-coil, the coupling between the coils was less than -32dB and SNR was increased. Using intraoral dipole design instead of loop improves patient comfort. We demonstrated feasibility of the intraoral dipole combined with an extraoral flexible coil-array for dental MRI. Dipole antenna enabled decreasing imaging field-of-view, and reduced the prevalent signal from tongue. This study highlights the advantages and the main challenges of the intraoral RF coils and describes a novel RF coil that addresses those challenges.

Dipole antenna design as hyperthermia applicator using CST microwave studio

Dipole antenna design as hyperthermia applicator using CST microwave studio

Model study of complex conductivity and permittivity of CNT/PANI composite (CPC) material for application of THz antenna

Nano-antenna in THz frequency range have eminent application in field of optoelectronics devices such as photovoltaic devices, Light emitting devices, detectors, bio-sensing devices and solar cell. Antenna made of metallic material faces challenges in THz frequency ranges. In this paper, author purpose the design model of composite material structure made of CNT enveloped with polyaniline (CPC). The mathematic model for measurement of complex conductivity, relative permittivity and plasma frequency are explored and formulated for new CPC material. The calculated results are further useful in design and EM analysis of dipole antenna by creating material library in antenna simulation tool.

Design and Analysis of High Gain Dual-polarized Dipole Antenna Based on Partially Reflective Metasurface

A partially reflective metasurface (PRMS) structure is proposed for dual-polarized dipole antenna with a high gain and wide broadband. Stable radiation patterns are realized by using quadrilateral bottom reflector. The phase bandwidth of PRMS structure reflection presented in this paper matches well with the antenna operating bandwidth. The gain of the dualpolarized antenna is improved to 10.2dBi at 1.8GHz by adjusting the size and height of PRMS structure. Meanwhile, the bandwidth is expanded (61.2%). Measured result demonstrates that the antenna has a stable beamwidth which is desirable in base station applications. Furthermore, the designed antenna can be used for communication in complex environment because of its excellent performance.

Graphene characterization based nano dipole antennas design for nano network wireless communication applications

Graphene-enabled nano antennas constitute a novel paradigm which is a current trend of research among designers. Graphene-based nano-antennas with nanometer in size have shown to radiate electromagnetic waves at the terahertz (THz) frequency band. Proposed research activity is an attempt of Terahertz Nano dipole antenna design through the Finite Difference Time Domain (FDTD) based numerical simulation software, i.e. CST. Graphene material as adipole antenna has been explored to get a radiation performance. Before hand absorption, reflection and transmission characteristics of the grapheme layer has been explored. Designed antenna is analyzed in terms of the reflection coefficient, and radiation pattern etc. An attempt has been done for resonance study of graphene based nano dipole antennas, in that patch antenna length parameteris changed and performance is observed. The impact of most crucial parameter, i.e., chemical potential on the grapheme radiation performance has been analyzed in terms of reflection coefficient. Proposed antenna may be suitable for wireless nano communication applications.

HF Wire-Mesh Dipole Antennas for Broadband Ice-Penetrating Radar

In this letter, a novel high-frequency to very-high-frequency wire-mesh dipole antenna design for use in polar regions is discussed and evaluated. The antenna was designed to be lightweight, readily demountable, and acceptably robust. This is an initial step in the development of a ground-based, phase-sensitive, synthetic aperture imaging system for use on an autonomous rover platform. The results of initial trials on the Rhone Glacier, Switzerland, in August 2019, are discussed, with particular attention being paid to the effect on the antenna performance of high surface water content. Including the effects of the surface water resulted in good agreement between field results, and modeled performance.

A Balun Bandpass Filter to Facilitate the Design of Dual-Polarized Dipole Antenna

A dipole antenna based on a balun bandpass filter (BPF) is developed in this paper. The balun BPF employs two U-shaped resonators settled on the left side of the open-circuited transmission line and two L-shaped stubs to produce signals with equal amplitude and inverse phase. In this way, the volume of the balun BPF is reduced by half, and the distance between two output ports is dramatically decreased. Then, the balun BPF is integrated with a dipole. Instead of the traditional Γ-shaped line with a wide balun ground, two thin microstrip lines with width of 1 mm are adopted to connect the dipole and the balun BPF. The antenna bandwidth is further extended due to the fusion of the resonance of the dipole and balun BPF. As a result, the proposed antenna can operate from 4350 to 5025 MHz (covering the n79 band of 5G NR, 4400 MHz–5000 MHz), yielding a good filtering performance in the stopband. The measured half-power beamwidth is ranging from 61° to 63° and the measured gain is ranging from 7.95 to 8.5 dBi in the passband. This new balun BPF and the dual-polarized dipole based on it have great potential to be applied in 5G MIMO systems.

Design of a Wideband Coupled Feed Dipole Antenna for PCL Array Systems

This article proposes the design of a wideband coupled feed dipole antenna for Passive Coherent Location (PCL) systems. The proposed antenna consists of an internal direct feed dipole and an external coupled feed dipole. This coupled feed mechanism, which is often used in microstrip patch antennas, is applied to the dipole element for a wide matching bandwidth. To verify the operating principle of the proposed antenna, an equivalent circuit model is investigated along with some parametric studies of the coupling effect. The proposed antenna is then extended to an eight-element uniform circular array to confirm the beamforming performance for PCL systems. The results demonstrate that the coupled feed dipole element is more suitable to enhance the matching bandwidth compared to a conventional dipole antenna.

A Method of Generating Radiation Nulls Utilizing Inherent Resonance Modes for Dual-Polarized Filtering Dipole Antenna Design

This communication proposes a method of generating radiation nulls for designing wideband dual-polarized filtering dipole antenna with simple structure. The proposed antenna consists of a pair of crossed dipole radiators, a ground plane, and a balun. Different from the previously proposed methods, the filtering performance of the proposed antenna is achieved by fully exciting the out-of-band resonance modes of the balun and radiator. The proposed dual-polarized filtering antenna has a very simple structure without any extra circuit and nearly has no radiation performance degradation. One radiation null and two other ones are generated at the lower and higher edges of the passband to achieve good frequency selectivity, respectively. The proposed antenna has high efficiency of about 90% inside the operating bandwidth of 1.7-2.8 GHz and out-of-band gain suppression of more than 20 dB.

Design of a single null compensation dipole antenna

In this paper, a single null compensation dipole antenna for Wi-Fi band (2.4 GHz) is developed. The antenna is fed by the parallel transmission lines, and its radiation unit consists of a printed dipole antenna and a Yagi antenna. The proposed antenna has three layers. The top and bottom layers are printed with the dipole antenna and the driver arm of the Yagi antenna. The director and the reflector of the Yagi antenna are placed on the middle layer. The three layers are separated by two FR-4 substrates. This antenna satisfies the omnidirectional radiation characteristic in its H plane and can compensate a null point in the E plane. Simulation results show that the 10 dB bandwidth is 2.32 to 2.46 GHz. The maximum realized gain is 1.13 dB in the frequency band. The non-roundness of the H plane is less than 2 dB, which shows good omni-directivity. A null point in the radiation pattern of the E plane is compensated to −1.4 dB at 2.4 GHz, while the other null point of the E plane remains below −15 dB. The antenna has been manufactured and tested, and the measurement results validate the design and the simulation results.

Design of a Qaudruple-arm UHF Dipole Antenna Fed by a Collinear Coaxial Cable

본 논문에서는 동일직선 동축선에 의해 급전되는 4-지선 H-형 UHF 대역 다이폴의 설계를 제시하였다. 다이폴 안테나는 인쇄형이며 인쇄회로기판 (PCB)의 한 면에 있는 2개의 상부 지선과 다른 면에 있는 2개의 하부지선을 가진다. 상부 및 하부 지선은 평행 스트립 전송선으로 급전되며 이는 다시 최적 설계된 변환부를 통하여 동일직선 동축선에 의해 급전된다. 다이폴의 H 모양의 형상으로 인해 동축선이 다이폴의 이득패턴에 미치는 영향은 작다. 패러미터 분석을 수행하고 이로부터 UHF 대역 4-지선 다이폴 안테나의 최적 설계를 얻었다. 설계된 다이폴 안테나는 885-1050 MHz에서 -10 dB 이하의 반사계수, 915 MHz에서 2.6 dBi의 최대이득, 전계면에서 반파장 도선 다이폴의 이득패턴과 2.9 dB 이하의 차이, 자계면에서 0.3 dB 이하의 이득 차이를 가진다.

Design and development of cross dipole antenna for satellite applications

Abstract In this paper, a cross dipole antenna is proposed, designed, and developed for satellite communication applications. The design incorporates an alternative feeding mechanism of the coaxial/probe feeding technique with balun. The primary objective of this paper is to develop the high gain antenna with an array configuration for satellite communication. The performance parameters of an antenna such as return loss, radiation pattern, gain and directivity are investigated for cross dipole antenna and 1 × 2, 1 × 4 array configurations. It operates for Ku band (12–18 GHz) and produces a high gain with low return loss. The proposed antenna has five useful bands and exhibits a peak directive gain of 13.21 dBi at 12.4 GHz with a bandwidth of 0.89 GHz. Additional bands are also offering a gain of 11.23 dBi with a bandwidth of 0.849 GHz at 10.6 GHz, 6.59 dBi with a bandwidth of 0.6 GHz at 11.5 GHz, 12.13 dBi with a bandwidth of 1.37 GHz at 14.2 GHz and 10.47 dBi with a bandwidth of 1.3 GHz at 15.8 GHz. The cross dipole antenna is analyzed for 1 × 2, 1 × 4 array configuration in order to improve the overall gain. The proposed antenna is fabricated on FR4 substrate with a dielectric constant of 4.4 and loss tangent (tan δ) of 0.007 with the thickness of 1.6 mm. The size of the proposed antenna is 72 × 84 mm. The proposed antenna meets the requirements of an antenna which is operating at Ku band; hence, it is found to be suitable for real time applications.

Impedance and Voltage Power Spectra of a Monopole Antenna in a Warm Plasma—Derivation and Application to CubeSats

AbstractThe impedance for a monopole antenna in a warm plasma is derived and compared with the cases for wire dipole and double‐sphere antennas. This derivation produces a new expression for the monopole antenna response function, Fm1(x), which is very similar to the double‐sphere antenna response function. The monopole, wire dipole, and double‐sphere response functions are compared by modeling an antenna in Earth's ionospheric plasma (i.e., electrostatic and collisionless) and predicting the antenna capacitance and voltage power spectra for quasi‐thermal noise (QTN) and shot noise. Specifically, we assume the antennas are part of a CubeSat, which has spurred this research as most interplanetary craft carry a dipole or more complicated antenna designs on board (Imbriale, 2006, https://doi.org/10.1002/0470052783.ch3; Imbriale, Gatti et al., 2006, https://doi.org/10.1002/0470052783.ch5). The monopole antenna current distribution is assumed to be a half‐triangular current distribution (considering only the positive half of the triangular distribution), which follows that of prior authors (Balmain, 1965, https://doi.org/10.6028/jres.069D.065; Kuehl, 1966, https://doi.org/10.1002/rds196618971; Couturier et al., 1981, https://doi.org/10.1029/JA086iA13p11127) and simplifies comparison. The predictions for the shot noise and capacitance presented problems, as the integral over wave number space or k space did not converge for large values of k. The derived expression therefore remains a current problem in these situations, and no alternative has been found in the existing literature, necessitating future work to determine a more general expression. In this paper we bring the problem of an appropriate analytic monopole antenna response function to the attention of the community and outline a number of tests that can be used to verify any future expression.

Design of a Dual-Polarized Magnetoelectric Dipole Antenna With Gain Improvement at Low Elevation Angle for a Base Station

A ±45° dual-polarized broadband magnetoelectric dipole antenna with gain improvement at low elevation angle is proposed in this letter for a base station. The proposed antenna covers 2.45–2.8 GHz, indicating a 13.3% impedance band. In order to improve the gain at ±60° angle, a notched metal wall is employed and the gain of the proposed antenna at ±60°angle is improved by 2 dB over the entire band compared with the original antenna. Moreover, the proposed antenna has good performances with stable radiation patterns, a front-to-back ratio around 20 dB and a cross-polarization discrimination over 15 dB. An antenna prototype is fabricated and measured for verification. A good agreement is met between the simulation and measurement and good performances make it a candidate for a 5G base station.

Design and Performance Prediction of a Dual-Band Coupled-Fed Dipole Array Antenna for PCL Systems in the VHF Band

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.