Search results for "Dipole antenna"
showing 10 items of 11 documents
Passive RFID Strain-Sensor Based on Meander-Line Antennas
2011
The processing of backscattered signals coming from RFID tags is potentially useful to detect the physical state of the tagged object. It is here shown how to design a completely passive UHF RFID sensor for strain monitoring starting from a flexible meander-line dipole whose shape factor and feed section are engineered to achieve the desired sensing resolution and dynamic range. This class of devices is low-cost, promises sub-millimeter resolution and may found interesting applications in the Structural Health Monitoring of damaged structures and vehicles as well as during extreme and adverse events.
A new bi-faced log periodic printed antenna
2005
In this paper, a new design of a broadband planar printed antenna based on the academic log periodic antenna is presented. The antenna consists of a series of printed dipoles, distributed on both faces of the substrate. Some configurations are explored, with a different number of printed dipoles. These are designed, simulated, fabricated, and measured. The calculated and measured return losses and radiation patterns are presented. The utility of the proposed antenna associated with its frequency bandwidth is better than 80%. The measured absolute gain is 6.5 dBi, and the front-to-back ratio is around 8 dB. The presented antenna should find wide applications in wireless communication systems…
Dual-band printed dipole antenna for Wi-Fi 802.11n applications
2010
A dual-band compact printed dipole antenna for Wi-Fi 802.11n applications in the 2.45 and 5.5 GHz bands is presented. The proposed antenna consists of two printed dipoles with the arms located onto both sides of the dielectric substrate and a bended stripline. This feed scheme makes easy the integration of the antenna with the electronic subsystem and avoids the radiation towards the device. For the design and optimisation, a specifically developed finite-difference time-domain based code is used. The antenna has then been fabricated, simulated and measured. The return losses highly match the Wi-Fi frequency specifications with a moderate gain (between 1 and 3 dBi) and efficiency better tha…
Detection of defective elements in an X band array antenna from its near field measurements
2007
An algorithm has been used to detect defective elements errors in array antennas. It has been applied to an X band slot array antenna and good results have been obtained. These have enabled the detection of errors in the manufacture process. We have used spherical near field measurements of the radiated field of the antenna. Then, once the equivalent currents are be obtained, an analysis of these results will be made in order to detect possible mistakes.
Novel plasmonic sensor design using plasmon-induced transparency
2010
We introduce a novel sensor concept in the field of plasmonics, namely plasmon-induced transparency sensors. These sensors combine localized particle plasmon resonances with extremely small sensing volume with excellent sharp spectral resonances that show a good respose to refractive index changes of the surrounding environment. The principle is based on the plasmonic analog of electromagnetically induced transparency (EIT) between a radiative dipole and a nonradiative quadrupole antenna. This effect yields a spectrally narrow resonance within a broad localized particle plasmon resonance in the near-infrared spectral region [1, 2]. Using deposition of biotin and streptavidin, we demonstrate…
Planar metamaterial analogue of electromagnetically induced transparency for plasmonic sensing.
2009
We experimentally demonstrate a planar metamaterial analogue of electromagnetically induced transparency at optical frequencies. The structure consists of an optically bright dipole antenna and an optically dark quadrupole antenna, which are cut-out structures in a thin gold film. A pronounced coupling-induced reflectance peak is observed within a broad resonance spectrum. A metamaterial sensor based on these coupling effects is experimentally demonstrated and yields a sensitivity of 588 nm/RIU and a figure of merit of 3.8.
Particle Plasmons as Dipole Antennas: State Representation of Relative Observables
2018
The strong interactions between light and plasmons (in metal nanoparticles) allow to observe chemical and physical processes on and around the particle on nanometer length scales as well as they al...
Design of a Compact Dual Circular-Polarized Antenna for L-Band Satellite Applications
2020
In this paper, we propose the design of a dual circular-polarized antenna for L-band applications (1.1-1.6 GHz). The designed antenna has been developed by considering crossed-dipoles on top of which a circular patch has been placed to properly act on the mutual coupling between the dipoles. The dual circular polarization is achieved by feeding dipoles in quadrature. Moreover, to increase the antenna gain and polarization purity at high elevation angles, a fence of passive monopoles has been added. The proposed antenna can profitably used as primary feed of a low-frequency parabolic reflector.
Broadband printed dipole with integrated via-hole balun for WiMAX applications
2010
A broadband balanced printed dipole antenna for WiMAX applications (2.5/3.6 GHz) is presented. An integrated via-hole balun is used to feed the antenna and a Yagi-like scheme is proposed to improve the gain. The design has been optimized by means of parametric FDTD simulations. The antenna was fabricated and measured, giving a bandwidth higher than 50% and a gain higher than 4 dBi. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:52–55, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25671
The Influence of a Magnetized Plasma Column on the Radiation Characteristics of a Strip Loop Antenna
2014
The radiation characteristics of a circular loop antenna located on the surface of an open waveguide in the form of an axially magnetized plasma column are studied using the rigorously obtained current distribution of such an antenna. The radiation resistance of the antenna excited by a time-harmonic external voltage is obtained for the case where the plasma inside the column is resonant. The distribution of the radiated power over the spatial spectrum of the excited waves is found and discussed.