Examinando por Autor "Arboleya, Ana"

Mostrando 1 - 10 de 10

Dual-Band and Dual-Polarized Reflectarray for Intelligent Reflecting Surface Applications in Millimeter-Wave 5G
(Institute of Electrical and Electronics Engineers, 2023-03) Cordente, Felipe; Martinez-de-Rioja, Eduardo; Arboleya, Ana; Encinar, José Antonio
In this work, a dual-band and dual-polarized reflectarray is proposed for non-tunable Intelligent Reflecting Surfaces (IRS) in millimeter-wave 5G. The reflectarray unit-cell has a dual-layer configuration, where the printed elements on each layer are designed to provide the required phase shifts at a different operating frequency (lower layer elements for 28 GHz and upper layer elements for 39 GHz). A 20 cm x 20 cm reflectarray panel has been designed to produce a collimated beam in dual-linear polarization at the 28 GHz and 39 GHz bands simultaneously. The proposed concept can be used to design passive IRS panels (without tunability) with dual-band operation, which can be used to improve coverage of dead zones or avoid obstacles that block direct communication links in millimeter-wave 5G networks.
Dual-Band Electromagnetic Skin with Independent Reflection Performance at 28 and 39 GHz for 5G Millimeter-Wave Communications
(Institute of Electrical and Electronics Engineers, 2024-07-15) Martinez-de-Rioja, Eduardo; Arboleya, Ana; Rodríguez Varela, Fernando; Fontá, Celia
This letter presents a dual-band Smart Electromagnetic Skin (SES) for millimeter-wave 5G applications, which provides simultaneous operation at the 28/39-GHz bands with independent reflection performance at each band (i.e., different incidence and reflection angles). The SES consists of a two-layer reflectarray panel of 202.5-mm side, which produces two independent reflected beams in dual-polarization when it is illuminated from two different feeders (one for each operating band). A prototype of the SES has been fabricated and tested, and the measured radiation patterns agree well with the simulations. The 2-dB gain bandwidth exceeds 14.3% at 28 GHz (26-30 GHz) and 5% at 39 GHz (38-40 GHz). The dual-band SES will contribute to enhance 5G communications by producing two independent reflected beams when it is illuminated from two faraway base stations, each operating at a different frequency
Dual-Band Reflectarray-Based Electromagnetic Skin to Provide Millimeter-Wave Coverage in the 28/60-GHz Bands
(Institute of Electrical and Electronics Engineers, 2024-03) Vallejo, Jorge; Martinez-de-Rioja, Eduardo; Arboleya, Ana
In this contribution, a low-profile dual-band smart electromagnetic skin (SES) is proposed to improve wireless communications in millimeter-wave 5G. The SES is based on a single-layer reflectarray panel that can operate simultaneously at the 28 and 60 GHz bands. The reflectarray unit-cell consists of a central lower frequency element which is surrounded by four higher frequency elements. The SES has been designed to provide a different coverage for each frequency (i.e., two separate beams with different pointing directions). A beamforming technique has been applied to broaden the beams in azimuth and achieve a wider coverage. The proposed device can be used to enable wireless communications in millimeter-wave 5G by providing enhanced coverage in nonline-of-sight (NLOS) scenarios.
Dual-Polarized Reflectarray for Coverage-Enhancing Applications in sub-THz 6G Networks
(2024 4th URSI Atlantic Radio Science Meeting, AT-RASC 2024, 2024-05) Feito-Rojo, Alejandro; Palací, Jesús; Martinez-de-Rioja, Eduardo; Arboleya, Ana
This contribution presents the design and simulation results of a dual-polarized reflectarray antenna for coverageenhancing applications in sub-THz 6G communication networks. A 68 mm x 68 mm reflectarray panel, comprising a planar array of 40 x 40 cells, has been designed to produce two independent beams in orthogonal linear polarizations at 100 GHz, in order to cover two different regions of mobile users. The beams have been broadened by the application of a beamforming technique to cover a wider angular region. The proposed design procedure can be applied to design passive reflectarrays for operation as base station antennas or reflecting intelligent surfaces, capable of improving wireless coverage in future sub-THz 6G systems.
Fast Planar Near-Field Measurements of Reduced Angular Pattern Domains
(Institute of Electrical and Electronics Engineers, 2024-07-15) Rodríguez Varela, Fernando; Arboleya, Ana; Fontá, Celia; Martinez-de-Rioja, Eduardo; Calatayud Maeso, Jorge
Emerging 5G and Beyond wireless systems are putting the focus on millimeter-wave (mmW) and sub-THz antenna systems with multiple beams and a large number of elements yielding electrically large and complex radiant systems such as Reflective Intelligent Surfaces (RIS) or Massive MIMO panels. Characterization of those antennas may be unfeasible by means of conventional near-field techniques due to the required sampling schemes and high acquisition times. This work proposes a fast Planar Near-Field (PNF) technique based on sparse acquisitions. Singular Value Decomposition (SVD) techniques are employed to reduce the number of unknowns of the inverse problem and to design a non redundant measurement grid. By restricting the near-field to far-field transformation problem to a reduced domain of the antenna radiation pattern, a time-efficient characterization of the mentioned antennas is achieved. The proposed technique has been validated through numerical an measurement examples demonstrating its potential for fast and robust PNF measurements of narrow beam antenna patterns with large tilt angles
Freehand System for Probe-Fed Antenna Diagnostics by Means of Amplitude-Only Acquisitions
(IEEE Transactions on Instrumentation and Measurements, 2024-03-01) Arboleya, Ana; Laviada Martínez, Jaime; Álvarez López, Yuri; Álvarez Narciandi, Guillermo; Las-Heras Andrés, Fernando; Luxey, Cyril; Titz, Diane; Bisognin, Ai
This article presents a system for easing the characterization of probe-fed antennas on available probe stations. Many of these stations were deployed for scattering parameter measurement but not for radiation pattern acquisition. Furthermore, these latter acquisitions have traditionally required the use of mechanical positioners for the automated movement of the probe antenna along different surfaces. Integration of these mechanical systems can be complex in some probe stations due to physical constraints. This work proposes an easy-to-deploy freehand system for amplitude-only field acquisitions providing great flexibility for probe-fed antenna diagnostics. In addition, the use of feeding probes, which can be bulky if compared to low-gain antennas is known to result in partial blocking avoiding the acquisition of the radiation pattern for some angles and for causing reflections yielding some ripple and distortion in the measured pattern. The system benefits from a near-field (NF) to far-field (FF) transformation based on the source reconstruction method so that unwanted reflections can be spatially identified and filtered out. Finally, broadband phaseless acquisition based on interferometry is implemented. This technique enables to alleviate the requirements of a full-vector (i.e., amplitude and phase) acquisition without losing information regarding the time-domain behavior and to retrieve all the frequencies simultaneously without losing the coherence between them so that parameters such as the delay spread can be measured. Simulated and experimental results in the V-band from 57 to 66 GHz are analyzed to validate the proposed system. Results are in fair agreement with both simulations and a direct FF acquisition on a conventional automated spherical system used as a reference.
FSS-Backed Reflectarray for Millimeter-Wave 5G Applications at the 28 GHz band
(2023-06) Soroka, Roman; Martinez-de-Rioja, Eduardo; Arboleya, Ana; Encinar, José Antonio
This contribution presents the design of a 30x30-element reflectarray antenna backed by a frequency selective surface (FSS) for millimeter-wave 5G applications at the 28 GHz band. The proposed FSS-backed reflectarray works identically to a conventional metal-backed reflectarray in the 28 GHz band, where it can be used to enhance millimeter-wave coverage. However, in other bands of 5G, such as sub-6 GHz and 39 GHz, the antenna behaves as a transparent structure, suppressing the specular reflections of impinging signals.
Reflectarray de doble banda y polarización dual para redes 5G de ondas milimétricas
(Comité Organizador y Científico XXXVIII Simposio Nacional de la Unión Científica Internacional de Radio, URSI23. Universidad de Extremadura, 2023-09) Cordente, Felipe; Martinez-de-Rioja, Eduardo; Arboleya, Ana; Encinar, José Antonio
In this contribution, a dual-band reflectarray that operates at 28 and 39 GHz is proposed for millimeter-wave 5G applications. The unit-cell of the reflectarray is based on a dual-layer configuration, where the printed elements on each layer are used to control the phase shift introduced at each operating frequency. A 20 cm x 20 cm reflectarray is designed to generate a collimated beam in dual-linear polarization (Horizontal and Vertical) simultaneously at 28 and 39 GHz. The proposed technology can be applied to design passive intelligent reflecting surfaces (IRS) with dual-band operation, which can be used in millimeter-wave 5G networks to improve the coverage of dead zones or avoid the obstacles that block direct point-to-point communications links.
Robotic Arm-based Antenna Measurement System
(Institute of Electrical and Electronics Engineers AP-S/URSI, 2024-07) Fontá, Celia; R. Varela, Fernando; Arboleya, Ana; Martinez-de-Rioja, Eduardo
An in house robotic arm-based antenna measurement system is presented. The need for a flexible measurement system to work at millimeter-wave bands (mmW) is the main motivation of this work. At the moment the system is programmed to perform planar acquisitions of 80mm×80mm up to 67 GHz. Post-processing techniques in order to reduce the effect of the non-anechoic environment and acquisition time have also been implemented. The system has been validated by means of measurements in the K-band with very good agreement with reference measurement performed in a spherical range in anechoic chamber.
Superficies Reflectoras de Doble Banda para Proporcionar Cobertura en Redes 5G de Ondas Milimétricas
(Comité Organizador y Científico XXXIX Simposio Nacional de la Unión Científica Internacional de Radio, URSI 2024. Escuela Politécnica de Cuenca. Universidad de Castilla-La Mancha, 2024-09) Martinez-de-Rioja, Eduardo; Vallejo, Jorge; Arboleya, Ana; Varela, Fernando, R.; Fontá, Celia
In this contribution, two designs of dual-band reflectarray surfaces are proposed for coverage-enhancing applications in millimeter-wave 5G networks. The first design is based on a two-layer reflectarray panel with simultaneous operation at 28 and 39 GHz, which is able to generate two independent collimated beams in dual polarization (one beam at each frequency). The second design is based on a single-layer reflectarray that operates at 28 and 60 GHz. In this case, a beamforming technique has been applied to broaden the beams in the azimuth plane, in order to cover a wider angular range. The proposed reflectarrays can be used to enable wireless communications in millimeter-wave networks, providing coverage of blind zones in both indoor and outdoor scenarios.