Programa del congreso

This work presents a newly designed antenna measurement facility aimed at enhancing the mm-wave measurement capabilities of UPM’s LEHA. The system comprises a three-axis planar scanner with polarization control, a spherical positioning system, and a reflector-based compact antenna test range (CATR) for mm-wave applications. All mechanical and electrical motion components were custom-designed to compete with commercial solutions. The motor control firmware was developed in-house using an embedded microcontroller with cascaded timers and a DMA coprocessor. The facility’s performance was validated through electrical and mechanical assessments of the spherical near-field range and CATR, demonstrating its capabilities for the W and G frequency bands.

With the advent of new cutting-edge applications such as extended reality, haptics systems or brain-computer interfaces; the future sixth-generation (6G) is expected to reach peak data-rates of about 1 Tbps and latencies below 1 ms. In order to meet these requirements, the recent literature is proposing indoor systems operating in the terahertz (THz) bands, which can provided extremely wide transmission bandwidths. However, these frequencies are not explorated enough in terms of propagation channel characterization. In this work we performed an study and modeling of the path-loss in two corridor scenarios for the ultra-wideband frequency range from 250 GHz to 330 GHz. We observe that path-loss increases log-linearly with distance from 70 dB to 130 dB. Additionally, for distances between transmitter and receiver greater than 7.2 m, an interference pattern appears due to specular components derived from walls and floor reflections. Finally, we apply a power-law model to the experimental path-loss obtaining loss exponents of 2.15 and 2.26; both larger than the expected for free-space.

This paper presents a multi-objective metaheuristic algorithm as a design method to achieve an optimized microstrip patch 2x4 array patch, targeting a resonant frequency of 26 GHz and 0.5 GHz of bandwidth. The optimization adjusts key design parameters through parametric space sampling and iterative evolution of tentative solutions. A Python script interfaces with CST Microwave Studio to automate geometry creation, simulation, and evaluation of two objectives: minimizing the reflection coefficient S11 at the target resonant frequency, and maximizing bandwidth, by ensuring a significant number of frequency points meet the requirement of S11 < -10 dB. The method is first applied to a single patch element, which serves as the foundational block for the array configuration. The array extension leverages the optimized patch parameters as a starting point, followed by a full re-optimization that incorporates array-specific design considerations such as inter-element spacing, phase compensation, gain, and sidelobe level. In order to approximate the Pareto front, the optimization algorithm evolved for 2,000 iterations for the single patch case and 6000 for the 2x4 array. This approach demonstrates the adaptability of this method for advanced 5G/6G antenna designs

Este artículo presenta los últimos avances en los sistemas de medida del laboratorio singular Smart Wireless Technologies, diseñados para la caracterización precisa de dispositivos radiantes y materiales por encima de 100 GHz, en el rango de subTHz. El avance de las comunicaciones ha impulsado la investigación y el desarrollo de dispositivos que operan a frecuencias cada vez más altas, lo que requiere métodos de medición más precisos, rápidos y eficientes. Para abordar estos desafíos, se han desarrollado soluciones innovadoras que minimizan pérdidas, optimizan los tiempos de prueba y mejoran la precisión de las mediciones. En este documento, se realiza una revisión de laboratorios nacionales con capacidades similares y se describen en detalle varios sistemas avanzados de medición del laboratorio singular. Entre ellos, destaca un sistema motorizado en cámara anecoica, diseñado para evaluar antenas con alta resolución espacial y espectral. Además, se presenta un sistema de caracterización de materiales en espacio libre y un sistema especializado para mediciones de Radar Cross Section (RCS), esenciales en aplicaciones de telecomunicaciones, defensa y detección. Estos sistemas mejoran las capacidades del laboratorio y lo posicionan como un referente en la caracterización electromagnética.

In this paper, we study the dynamic formation of transients when plane waves impinge on a dispersive slab that abruptly changes its electrical properties in time. The

timevarying slab alternates between air and metal-like states, whose frequency dispersion is described by the Drude model. It is shown how the physics of this complex system can be well described with the joint combination of two terms: one associated with temporal refractions and the other associated with spatial refractions. To test the validity of the approach, some analytical results are compared with a self-implemented finite-difference

time-domain (FDTD) method. Results show how the transients that occurred after the abrupt temporal changes can shape the overall steady-state response of the space-time system. In fact, far from always being detrimental, these transient states can be conveniently used to perform frequency conversion or to amplify/attenuate the electromagnetic fields.