Cross Dipole Research Articles

A Versatile Shared-Aperture Antenna for Vehicle Communications

This communication introduces a versatile, multi-service, shared-aperture antenna system for multiple vehicle applications. The design comprises three antenna elements: a rotatable microstrip antenna for global positioning system (GPS) communication, a cross-dipole circularly polarized antenna for satellite communication in the S-band, and a pattern reconfigurable antenna for V2V (vehicle-to-vehicle) communication. These antennas collectively support GPS, satellite communication (Satcom), and V2V communication in a single, shared-aperture design. This shared-aperture antenna system offers cost savings and occupies less space compared to using separate antennas for each service. The microstrip antenna covers the 1575 MHz frequency band used for GPS communication. The cross-dipole circularly polarized antenna provides continuous wideband coverage for S-band satellite communication. The pattern reconfigurable antenna, tailored for the specific application scenario, covers the 5.9 GHz V2V working frequency band (5.855–5.925 GHz). Practical testing and simulation results confirm the effectiveness of this antenna system for the intended applications. In summary, the microstrip antenna has a bandwidth of 1.565–1.578 GHz and a realized gain of 7 dBi with radiation efficiency of 81%, the cross-dipole antenna has a bandwidth of 2.2–3.8 GHz (53.3%) and a realized gain of 8.3 dBi with radiation efficiency of 90%, and the pattern reconfigurable antenna has a 5.8–6 GHz bandwidth and a realized gain of 3.7 dBi with radiation efficiency of 85%, and the isolation between antennas with different frequencies is 25 dB, 20 dB, and 30 dB in three frequency bands.

Compact Ultrawideband Circularly Polarized Crossed-Dipole Antenna With Post Fence and Parasitic Elements

Compact Ultrawideband Circularly Polarized Crossed-Dipole Antenna With Post Fence and Parasitic Elements

Dipole acoustic remote detection (ARD) logging and its application in fracture-cave reservoir

Abstract Oil and gas from deep reservoirs are mostly enriched in the fracture-cave reservoirs. For this reason, fine evaluation of large-scale fracture-cave and effective detection of small scale fracture-cave are the key issues to be solved in the exploration of fracture-cave type carbonate reservoirs. The acoustic remote detection logging technology is based on acoustic reflection method to continuously image the formation around the well. The cross dipole array sonic data can be processed to image geological anomalies within a range of about 20 meters outside the well. Dipole S wave remote detection has the remarkable advantages of low emission frequency and larger investigation depth, but it has 180 degrees’ azimuthal ambiguity. This study is based on previously developed far field dipole S wave remote detection tool, finite difference is performed on formation models with and without are obtained for representative fracture-cave formations and remote detection processing and interpretation software is updated. These are applied on a well in the northwestern area. Through the comprehensive analysis of remote logging, conventional logging, electrical imaging logging and seismic data of the fracture-cave geological anomalies, a fine picture of the morphology and development of the geological anomalies from the near wellbore to the far end is formed

A Circularly Polarized Antenna Based on Narrowed Crossed Dipole for Smartphone Satellite Communication

A Circularly Polarized Antenna Based on Narrowed Crossed Dipole for Smartphone Satellite Communication

Gravitationally controlled passive beam steering of a printed cross dipole antenna

AbstractIn this study, the design and characterization of a printed cross‐dipole antenna with a gravitationally controlled passive beam steering technique has been presented. The steering of the beam is achieved by using a floating reflector that remains parallel to the earth surface when the antenna along with the mounted body gets inclined while traveling through uneven roadways. Initially, the microstrip cross dipole antenna is designed and simulated along with the reflector to operate in one of the allocated 5G frequency bands of 2.6 GHz. This is followed by the fabrication of the antenna prototype along with a glass chamber where the reflector is kept floated over the fluid. Measurements are carried out and are in good comparison with that of the simulated one. This presented work can be a potential passive beam steering technique that can be used for surface‐to‐air communication systems.

A Wideband Circularly Polarized Dipole Antenna with Compact Size and Low-Pass Filtering Response.

This paper presents a compact wideband circularly polarized cross-dipole antenna with a low-pass filter response. It consists of two pairs of folded cross-dipole arms printed separately on both sides of the top substrate, and the two dipole arms on the same surface are connected by an annular phase-shifting delay line to generate circular polarization. A bent metal square ring and four small metal square rings around the cross-dipoles are employed to introduce new resonant frequencies, effectively extending the impedance and axial-ratio bandwidth. Four square patches printed on the middle substrate are connected to the ground plane by the vertical metal plates in order to reduce the antenna height. Thus, a compact wideband circularly polarized antenna is realized. In addition, a transmission zero can be introduced at the upper frequency stopband by the bent metal square rings, without using extra filter circuits. For verification, the proposed model is implemented and tested. The overall size of the model is 90mm×90mm×33mm (0.37λ0×0.37λ0×0.14λ0; λ0 denotes the center operating frequency). The measured impedance bandwidth and 3 dB axial-ratio (AR) bandwidth are 53.3% and 41%, respectively. An upper-band radiation suppression level greater than 15 dB is realized, indicating a good low-pass filter response.

Ultra-Wideband Dual-Circularly Polarized Crossed-Dipole Antenna With Stripline Coupler and Parasitic Elements for Vehicular Sensing and Communications

Ultra-Wideband Dual-Circularly Polarized Crossed-Dipole Antenna With Stripline Coupler and Parasitic Elements for Vehicular Sensing and Communications

Robust broadband dual-polarized rectenna with high conversion efficiency

In this paper, a robust wide-beam dual-polarized broadband rectenna with high conversion efficiency is proposed. First, a metal wall-loaded broadband cross-dipole antenna is designed as the receiving antenna. With the metal wall, the bandwidth of the receiving antenna is greatly improved. The measured results show that the −10 dB impedance bandwidth is 820 MHz from 1.65 to 2.47 GHz, and the 3-dB beamwidth is over 80° within the operating bandwidth. Besides, a novel impedance matching network is introduced to help the rectifier achieve high conversion efficiency in a wide bandwidth. The measured results show that the RF-DC conversion efficiency is maintained above 50 % with a maximum of 78 % within the bandwidth from 1.56 to 2.53 GHz when the load impedance is 840 Ω and the input power is 12.0 dBm. Finally, the receiving antenna and rectifier are integrated and measured. The results illustrate that the proposed design can be robustly against dynamic ambient power density, large oblique incidence angle, and arbitrarily polarized wave. Specifically, the measured conversion efficiency is over 49 % at an ambient power density of 200 μW/cm2 within the incident angle from −40° to 40° under arbitrary polarization. Hence, it could be a feasible solution to wireless energy harvesting (WEH) applications.

A Low-frequency Compact Lightweight Dual-polarization CATR Feed Antenna

To address the issue of a large axial distance for low-frequency feed antennas, this paper presents a low-frequency compact lightweight dual-polarization CATR feed antenna. This feed antenna consists of a near-rhombus-shaped crossed dipole antenna with chamfers, a third-order horn enclosure, and a novel feed network based on 180° hybrid couplers. Through design, the axial length of this feed source is approximately 290mm. The VSWR is less than 1.5, the HPBW is greater than 44.5° from 300MHz to 500MHz. The phase centre varies less than 0.3λ and the cross-polarization isolation is below in the whole working frequency band.

Design of 2.45 GHz High-Efficiency Rectifying Circuit for Wireless RF Energy Collection System.

A 2.45 GHz high-efficiency rectifying circuit for a wireless radiofrequency (RF) energy collection system is proposed. The RF energy collection system is composed of a transmitting antenna, a receiving antenna, a rectifying circuit and a load. The designed receiving antenna is a kind of dual-polarised cross-dipole antenna; its bandwidth is 2.3-2.5 GHz and gain is 7.97 dBi. The proposed rectifying circuit adopts the technology of an output matching network, which can suppress the high-harmonic components. When the input power at 2.45 GHz is 13 dBm and the load is 2 kΩ, the highest conversion efficiency of RF-DC is 74.8%, and the corresponding maximum DC output voltage is 4.92 V. The experiment results are in good agreement with the simulation results, which shows a good application prospect.

A Broadband Circularly Polarized Crossed-dipole Antenna with Wide Axial-ratio and Gain Beamwidths

A Broadband Circularly Polarized Crossed-dipole Antenna with Wide Axial-ratio and Gain Beamwidths

Broadband Circularly Polarized Printed Crossed-Dipole Antenna and Its Arrays for Cellular Base Stations

Broadband Circularly Polarized Printed Crossed-Dipole Antenna and Its Arrays for Cellular Base Stations

Dual‐band sub‐6‐GHz frequency filtering with optically transparent single‐layer dual‐polarized smart surface

AbstractOptically transparent dual‐band frequency‐selective surfaces (FSSs) are promising candidates to address the specific design challenges of the Internet of Things. This paper demonstrates their potential by discussing different configurations of the two single‐layer FSS designs on an innovative optically transparent polyvinyl chloride surface material. First, FSS cells consist of two cross dipoles placed forming angles of , where each rotated dipole structure parallel to the other. Then, in the second design, each one of the two cells is mirrored to enable polarization control for each band. As a proof‐of‐concept, five prototypes of each design having a unit cell size of are fabricated through a combination of cost‐effective printing and shearing. The manufactured prototypes yield more than 93% transparency and robust dual‐band performance. Moreover, more than 20 and 40 dB isolation for lower‐ and upper‐frequency bands are achieved from the fabricated prototypes. High‐transparency, cost‐effectiveness, and robust high performance in terms of suppression make both structures suitable for sub‐6‐GHz fifth generation applications.

LTCC-Based Dual-Polarized AiP Module by Multilayered Cross-Dipole Antennas for 5G Mobile Terminal Applications at 28 GHz Band

LTCC-Based Dual-Polarized AiP Module by Multilayered Cross-Dipole Antennas for 5G Mobile Terminal Applications at 28 GHz Band

A Compact Broad Circularly Polarized Cross-Dipole Antenna with Grounded Parasitic Elements

A new wideband cross-dipole antenna (CDA) with a circularly polarized (CP) characteristic is proposed in this article. The antenna consists of four L-shaped patches, two modified trapezoid-microstrip lines as an impedance tuner, a pair of vacant-quarter feeding loops as a continuous-phase feeding network, and four grounded inverted L-shaped strips as parasitic elements. It is noticed that the grounded inverted L-shaped strips are inserted directly below the L-shaped patches to increase the CP bandwidth and enhance the gains of the antenna, which is different from the conventional parasitic elements. First, a pair of vacant-quarter feeding loops is used as a feeding structure to provide a sequential phase characteristic. Second, four L-shaped patches as driven elements are connected to the feeding structure to excite two CP resonant modes. Third, two modified trapezoid-microstrip lines are inserted into the feeding structure to adjust the impedance match. Moreover, four grounded inverted L-shaped strips are introduced into the square reflector to achieve wider CP operation by utilizing a gap capacitive coupling feeding way. Finally, the proposed antenna is simulated, manufactured, and measured to verify the design rationality. The measured results indicate the proposed antenna has a broad 3-dB ARBW of 82.5% (1.38–3.32 GHz, 2.35 GHz) and a wide −10-dB IBW of 81.2% (1.18–3.04 GHz, 2.29 GHz). Furthermore, the measured and simulated CP bandwidths are 75.1% (1.38–3.04 GHz, 2.21 GHz) and 74.7% (1.36–2.98 GHz, 2.17 GHz), which is suitable for CP applications in WiBro (2.3–2.39 GHz) and GPS (L1 1.575 GHz) bands.

A Novel Broadband ± 45° Dual-Polarized Cross-Dipole Antenna with Multimode Resonance

A novel broadband ± 45 ° dual-polarized cross-dipole antenna is presented for application in 2G, 3G, 4G, and sub-6 GHz 5G base station. A bent structure with a coplanar transmission line is used in the antenna design, which achieves multimode resonance, broadening the impedance bandwidth tremendously. Especially, it can work at 3 λ / 2 and 2 λ resonant modes without the impact of reverse current. The antenna covers the frequency spectra from 1.7 GHz to 3.8 GHz with an enhanced impedance bandwidth of roughly 76.4% and VSWRs < 1.65 at two ports. A gain of 8.3 ± 1.9 dBi and port-to-port isolation > 22.5 dB are attained in the operating frequency range. Additionally, the presented antenna has a very simple configuration and is easy to construct. A mechanical prototype of the antenna has been manufactured and measured. The experimental findings and the computational results are in good agreement.

A Compact Circularly Polarized Crossed Dipole Antenna with Wide Bandwidth using Split Ring Resonator and Parasitic Patches

A new compact broadband circularly polarized (CP) crossed dipole antenna using split ring resonator (SRR) and parasitic patches are presented. The proposed antenna is mainly composed of two orthogonal strip dipoles, two 90∘ phase delay lines, four SRRs, and four parasitic patches. The combination of the orthogonal strip dipoles and the delay lines forms a crossed dipole as the main CP radiator. The well-designed SRR can extend the current path and improve the current distribution of high-frequency without increasing the size of the antenna, thereby reducing the size of the antenna and increasing the axial ratio (AR) bandwidth of the high-frequency. The introduction of parasitic patches can improve the current distribution between the upper and lower cut-off frequency points of the bandwidth, and make up for the defects of the insufficient bandwidth of the crossed dipole and the SRR, thereby realizing broadband CP radiation. To verify the antenna, a physical prototype is fabricated. The measured results show that the impedance bandwidth (IBW) of 69.1% (1.38-2.84 GHz), and a wide AR bandwidth of 57.7% (1.43-2.59 GHz). In addition, the designed antenna achieves a stable gain in the working band and a certain band-edge selectivity. Such a single-fed, simple structure and the wideband CP antenna is an excellent candidate for communication systems such as ISM (2.4 GHz), WiBro (2.3-2.39 GHz)and Inmarsat.

A Transmissive Metasurface Generating Wideband OAM Vortex Beam in the Ka-Band

In this paper a wideband transmitting metasurface is proposed to generate the orbital angular momentum (OAM) vortex beam in the Ka-band. The proposed unit cell is a novel combination of dual-square loops and a cross dipole element printed on four dielectric layers separated by an airgap. This combination of two types of elements helps to attain a linear transmission phase response with more than a 360 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{\circ }$</tex-math></inline-formula> phase compensation range with a transmission magnitude equal to or better than 1.1 dB. The proposed structure of the unit cell is also suitable for dual polarized applications due to its symmetrical configuration. The proposed metasurface is also fabricated and measured to verify its simulated performance. The overall measured outcome shows that the proposed structure has successfully achieved wideband performance for the OAM vortex beam with +1 mode. The overall mode purity is greater than 72% from 28.0 to 38.0 GHz, which is about 33.3% OAM bandwidth. Moreover, the peak gain of 23.8 dBi is achieved with 22.1% aperture efficiency.

A Novel Bow-Tie Balun-Fed Dual-Polarized Crossed Dipole Antenna

A broadband dual-polarized crossed dipole antenna is proposed in this paper. To achieve a wide impedance bandwidth and low-profile configuration, a novel bow-tie balun is applied to this antenna. Firstly, the working mechanisms of both bow-tie baluns and the antenna are introduced. Then, the parametric study and design guidelines are presented. Finally, the optimized antenna is fabricated, measured, and analyzed. The simulated and measured results show that the antenna has a wide impedance bandwidth from 2.42 GHz to 6.48 GHz. The fractional bandwidth is 91.2%. Moreover, within the whole band, the E-plane and H-plane radiation patterns are stable. The port isolation is greater than 20 dB, and the cross-polarization discrimination ratio is better than 25 dB. The proposed antenna achieves a realized gain of 7.5 dBi ± 0.5 dBi. It can be a good candidate for sub-6 GHz wireless communications or short-range radar applications.

A Dual-Circularly Polarized Wideband Dipole Antenna With Stable Axial-Ratio and Half-Power Beamwidths

With wide impedance bandwidth (IBW), wide axial-ratio bandwidth (ARBW), stable AR beamwidth, and stable half-power beamwidth (HPBW), a dual-circularly-polarized (DCP) crossed-dipole antenna is proposed. Each dipole consisting of two patches is fed by a pair of parallel transmission line, leading to a wide IBW. To enhance the ARBW and AR beamwidth, a quadrature wideband coupler is used, and the overlapping bandwidth of IBW and ARBW is up to 100%. The quadrature coupler is integrated with two pairs of parallel transmission line, and are printed on two substrates, which are squeezed into the space between the radiators and reflector, resulting into a compact antenna structure. With a total height of 0.016 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</sub> , a prototype is fabricated and measured, showing 1.5-VSWR IBW of larger than 104% for both Left-handed CP (LHCP) and Right-handed CP (RHCP), 3-dB ARBW of up to 100% both for LHCP and RHCP, and port-to-port (polarization) isolation of lager than 30 dB in 1.70 - 2.82 GHz, so the effective bandwidth (EBW) is about 50% (1.70 - 2.82 GHz). 3-dB AR beamwidth of 76° ± 5°, stable DCP characteristics with average gain of 7.2 dBi and HPBWs of 67° ± 4° are achieved.