Listar por tema "Antennas"
Mostrando ítems 1-20 de 24
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Advanced feeds for mm-wave antenna systems
Millimeter-wave antenna systems have traditionally required high performance feeds in order to fulfill its stringent requirements. Therefore, this goal has been achieved by corrugated horns. However, in the last years new ... -
A comprehensive survey of 'metamaterial transmission-line based antennas: design, challenges, and applications'
In this review paper, a comprehensive study on the concept, theory, and applications of composite right/left-handed transmission lines (CRLH-TLs) by considering their use in antenna system designs have been provided. It ... -
A comprehensive survey on 'circular polarized antennas' for existing and emerging wireless communication technologies
Circular polarized (CP) antennas are well suited for long-distance transmission attainment. In order to be adaptable for beyond 5G communication, a detailed and systematic investigation of their important conventional ... -
Design of antennas based on metasurfaces at millimeters and terahertz waves
Esta tesis presenta la evolución de una línea de investigación guiada por el desarrollo de estructuras metálicas para mejorar las propiedades de radiación de dispositivos que operan en ondas milimétricas (mmWaves). Cubre ... -
Development of ultrathin metasurface and partially reflective surface antennas for space applications
La industria espacial ha estado siempre muy interesada en la evolución de las antenas que se integran en los satélites. Se buscan soluciones que además de ser ligeras y compactas, tengan un coste reducido. De esta forma ... -
Dual circularly polarized broadside beam metasurface antenna
This paper presents the design of a modulated metasurface (MTS) antenna capable to provide both righthand (RH) and left-hand (LH) circularly polarized (CP) boresight radiation at Ku-band (13.5 GHz). This antenna is based ... -
Dual-polarized highly folded bowtie antenna with slotted self-grounded structure for sub-6 GHz 5G applications
In this paper, a novel dual-polarized highly-folded self-grounded Bowtie antenna that is excited through I-shaped slots is proposed for applications in sub-6GHz 5G multiple-input-multiple-output (MIMO) antenna systems. The ... -
Enhancing the quality of amplitude patterns using time-multiplexed virtual acoustic fields
Ultrasonic fields can push and levitate particles, heat up materials, induce contactless tactile stimuli, or affect the blood-brain barrier. Current phased-arrays can create dynamic amplitude patterns, but their quality ... -
Experimental validation of a Ku-band dual circularly polarized metasurface antenna
The experimental validation of a Ku-band dual circularly polarized (CP) broadside-beam metasurface (MTS) antenna is presented. A radially modulated anisotropic single layer MTS has been synthesised employing sub-wavelength ... -
A frequency reconfigurable compact planar inverted-F antenna for portable devices
In this paper, a low-profile, compact size, inexpensive, and easily integrable frequency reconfigurable antenna system is proposed. The proposed antenna consists of an inverted-F shape antenna, capacitors, and switching ... -
A gap waveguide fed circular polarization antennas in the millimeter wave range
In this work, a novel circular polarization (CP) antennas in ridge gap waveguide (RGW) working in the V-band of the millimeter-wave spectrum is presented. CP is generated in a simple and effective way by means of two ... -
Improved adaptive impedance matching for RF front-end systems of wireless transceivers
In this paper an automatic adaptive antenna impedance tuning algorithm is presented that is based on quantum inspired genetic optimization technique. The proposed automatic quantum genetic algorithm (AQGA) is used to find ... -
Low profile THz periodic leaky-wave antenna
In this work, a 0.566THz flat leaky-wave antenna, consisting of a central λ0/2 slot surrounded by straight parallel wedge corrugations, is numerically and experimentally analyzed. Simulations show a moderately high gain ... -
Metal 3D printing for RF/microwave high-frequency parts
Space Systems have been historically characterised by high performance, high reliability and high cost. Every new generation of space systems tends to improve performance, keep as much as possible reliability, speeding ... -
A metasurface-based single-layered compact AMC-backed dual-band antenna for off-body IoT devices
In this article, a compact printed monopole dual-band antenna using artificial magnetic conductor (AMC)-plane with improved gain and broader bandwidth, applicable for off-body internet of things (IoT) devices is presented. ... -
Optimum power transfer in RF front end systems using adaptive impedance matching technique
Matching the antenna’s impedance to the RF-front-end of a wireless communications system is challenging as the impedance varies with its surround environment. Autonomously matching the antenna to the RF-front-end is therefore ... -
Research on metamaterials for antenna applications
During the last 20 years a lot of attention has been paid to apply Electromagnetic Band Gap (EBG) technology in different frequency ranges, from microwaves to optics. EBG technology is based on the use of periodic structures ... -
A slow light fishnet-like absorber in the millimeter-wave range
A novel route to achieve a narrowband free-space electromagnetic absorber in any range of the spectrum based on stacked subwavelength hole arrays is proposed. The absorption is obtained by means of a slow light mode inside ...