Programa del congreso

Las antenas eléctricamente pequeñas, que resultan una necesidad en determinadas aplicaciones y frecuencias, suponen un desafío de diseño debido a su impedancia altamente reactiva y su baja resistencia de radiación. El uso de técnicas de adaptación tradicionales basadas en elementos pasivos impone un trade-off entre ancho de banda y eficiencia de radiación. Sin embargo, el uso de elementos activos permite superar los límites de Bode-Fano-Youla y obtener anchos de banda elevados sin con ello reducir drásticamente la eficiencia de la antena. En este paper se utiliza esta idea para adaptar un array logoperiódico de 2.3 GHz empleando un conversor de impedancia negativa para obtener elementos non-Foster (condensadores e inductores negativos) y crear una nueva banda a 300 MHz.

Wireless Power Transfer (WPT) plays a critical role in several future applications such as IoT sensors and medical implants. Efficient antennas are essential components to have higher performance for the WPT system working with a larger coverage area. This paper presents a novel high-gain omnidirectional conical dielectric resonator antenna (DRA) designed for WPT systems operating at 5.8 GHz. The proposed DRA features a conical geometry led by a short-circuited parasitic metallic circle patch, which enhances current distribution and significantly improves radiation efficiency. This enables the achievement of an omnidirectional pattern with a high peak gain of 4.26 dBi and high with a low ripple level below ±0.3dB. The antenna achieves a 4% impedance bandwidth and maintains omnidirectional radiation patterns in the azimuth plane with an impressive total efficiency of 95.1%. This design offers a compact and efficient solution for modern WPT applications requiring robust and uniform coverage.

This article presents the design and analysis of a floating patch antenna with symmetrical radiation pattern using dual-rod feeding. The design of floating patches using air as a dielectric and fed through a copper rod not only enables high efficiency and bandwidth but also significantly simplifies the manufacturing process. However, antennas designed with a single copper rod feed do not have a broadside radiation pattern due to the asymmetry of the feed, which is a known issue in patch radiation patterns and complicates its use in different applications. At the same time, the proposed symmetric feeding with two posts will produce an additional benefit, and the resulting floating structure will be more stable and robust, being the antennas developed with the feeding that is proposed in this contribution suitable for applications where vibrations could damage the patch supported with a single post. Therefore, the objective of this article is to present a floating patch design with a pure broadside radiation pattern that facilitates the use of this antenna in different applications, especially in the design of antenna arrays with a broadside radiation pattern or in devices where a robust layout is required.

This paper introduces the design of a circularly-polarized Gap Waveguide-based antenna. The design features a compact all-metal two-layered structure. It achieves circular polarization in a dual-band configuration, from 37.5 to 42.5 GHz and from 47.5 to 52.4 GHz, showing Axial Ratio values below 1.5 dB. The design includes a transition from a WR-19 standard waveguide to the Ridge Gap Waveguide that feeds the radiating structure. Regarding the return losses, values higher than 10 dB are achieved from 37.5 to 52.4 GHz. This unit cell antenna achieves gain values varying between 8.5 to 11.9 dB across the bands of interest.

Este trabajo presenta una técnica iterativa de muestreo adaptativo para medidas en rango plano con un brazo robótico. Esta técnica reduce el número de muestras sin disponer de información a priori de la antena. El método emplea una transformación matricial de campo cercano a campo lejano y Descomposición en Valores Singulares (SVD) para proyectar el campo en la apertura sobre sus modos dominantes. En cada iteración, se calcula y se añade un nuevo conjunto de puntos de muestreo que maximiza la variación en los coeficientes modales. La técnica ha sido validada mediante simulación a 30 GHz y mediante un ejemplo aplicado a una medida real a 22 GHz, obteniendo un 90% de reducción y un nivel de error de −47 dB en simulación, y 86% de reducción con un nivel de error de −38 dB para el ejemplo aplicado a medida real.