Open Access
Diseño de filtros en tecnología de línea coaxial sin dieléctricos mediante impresión 3D
(Universidad de Castilla La Mancha, 2024) Pons Abenza, Alejandro; Arregui Padilla, Iván; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Álvarez Botero, Germán Andrés; Martín Iglesias, Petronilo; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
This article presents the design and manufacturing of a fully metallic X-band bandpass filter in coaxial-line technology. The device is 3D-printed as a self-supported structure without any dielectric inside. A short-circuit λ/4 parallel stub bandpass filter provides the required mechanical support for the self-supported 3D-printing process. To enhance filter out-of-band performance, a second stage consisting of a stepped-impedance low-pass filter is integrated, also using coaxial-line technology. Both filters are designed separately and then combined to achieve desired frequency specifications. A prototype with a passband at X-band (between 8 and 12 GHz) is manufactured using Selective Laser Melting, showing excellent agreement between simulations and measurements. This approach promises highly integrated, multifunctional monoblock coaxial filters with additional benefits such as increased RF shielding and protection against electrostatic discharge.
Open Access
Gap waveguide topology with reduced height pins for millimeter-wave components
(URSI Publications, 2022) Santiago Arriazu, David; Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Arregui Padilla, Iván; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
A new topology for groove gap waveguide (GGW) technology is proposed to ease its manufacturing process by computer numerical control (CNC) milling. GGW technology consists of two metal plates, where one of them presents a λ/4 height pin bed that avoids contact with the other plate, making it an ideal alternative to other waveguides for millimeterwave applications. However, the manufacture of the pins by CNC milling may be troublesome due to the large pin height required. A GGW with reduced height pins will be proposed, maintaining the standard dimensions of the equivalent rectangular waveguide ports and the operation bandwidth. The performance of this new topology will be compared with other proposals by means of simulations and measurements, and a bandpass filter will be also implemented and manufactured in this technology to validate its usefulness.
Open Access
Passive microwave component design using inverse scattering: theory and applications
(Hindawi, 2013) Arnedo Gil, Israel; Arregui Padilla, Iván; Chudzik, Magdalena; Teberio Berdún, Fernando; Lujambio Genua, Aintzane; Benito Pertusa, David; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
We briefly review different synthesis techniques for the design of passive microwave components with arbitrary frequency response, developed by our group during the last decade. We provide the theoretical foundations based on inverse scattering and coupledmode theory as well as several applications where the devices designed following those techniques have been successfully tested. The main characteristics of these synthesis methods are as follows. (a) They are direct, because it is not necessary to use lumpedelement circuit models; just the target frequency response is the starting point. (b)They are exact, as there is neither spurious bands nor degradation in the frequency response; hence, there is no bandwidth limitation. (c) They are flexible, because they are valid for any causal, stable, and passive transfer function; only inviolable physical principles must be guaranteed. A myriad of examples has been presented by our group in many different technologies for very relevant applications such as harmonic control of amplifiers, directional couplerwith enhanced directivity and coupling, transmission-type dispersive delay lines for phase engineering, compact design of high-power spurious free low-pass waveguide filters for satellite payloads, pulse shapers for advanced UWB radar and communications and for novel breast cancer detection systems, transmission-type Nth-order differentiators for tunable pulse generation, and a robust filter design tool.
Open Access
Diseño de filtro en guía de onda en banda W mediante guía multicapa con simetría glide
(URSI, 2023) García-Martínez, Sergio; Santiago Arriazu, David; Tamayo-Domínguez, Adrián; Sánchez-Olivares, Pablo; Arregui Padilla, Iván; Lopetegui Beregaña, José María; Fernández González, J. M.; Gómez Laso, Miguel Ángel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
Este artículo presenta el diseño e implementación de un filtro paso banda de cuarto orden en tecnología de guía de onda multicapa a 100 GHz. Para evitar fugas de campo en las paredes de la guía y permitir la implementación del filtro en múltiples capas sin necesidad de contacto eléctrico, se ha utilizado una estructura periódica con agujeros y simetría de deslizamiento, con agujeros circulares, como una estructura de banda prohibida electromagnética (EBG). Se presenta un filtro robusto y compacto, capaz de mantener una buena respuesta en la banda para un amplio rango de entrehierro entre capas. Este enfoque permite la implementación de la estructura compleja del filtro en bandas milimétricas, ofreciendo alta precisión y facilidad de fabricación.
Open Access
Producing and exploiting simultaneously the forward and backward coupling in EBG-assisted microstrip coupled lines
(IEEE, 2016) Percaz Ciriza, Jon Mikel; Chudzik, Magdalena; Arnedo Gil, Israel; Arregui Padilla, Iván; Teberio Berdún, Fernando; Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, a methodology is proposed for the design of EBG-assisted coupled line structures in microstrip technology, controlling independently the forward and backward coupling. It is based on the use of a single-frequency-tuned electromagnetic bandgap (EBG) structure to produce a single backward-coupled frequency band, in combination with the forward-coupled frequency bands produced by the difference between the even and odd mode propagation constants present in microstrip technology. Thus, the central frequency of the backward-coupled band is controlled by the period of the EBG structure, while the frequencies of the forward coupled bands are fixed by the length of the device. The rest of the frequencies go to the direct port giving rise to a device with the input port matched at all the frequencies and where the coupled bands are easily controllable by adjusting the corresponding design parameter. The novel methodology proposed has been successfully demonstrated by designing a triplexer intended for the GSM (900 MHz) and WLAN (2.4 GHz and 5.5 GHz) telecommunication bands.
Open Access
Design procedure for new compact waffle-iron ilters with transmission zeros
(IEEE, 2018) Teberio Berdún, Fernando; Percaz Ciriza, Jon Mikel; Arregui Padilla, Iván; Martín Iglesias, Petronilo; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Arnedo Gil, Israel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In this paper, a novel waffle-iron filter with transmission zeros at multiple frequencies, along with its design procedure, is presented. The proposed filter features a high-power behavior and a wide rejected band in a single compact structure by means of a set of transmission zeros that can also be placed close to the passband. Its design method rests on a divide-and-rule strategy, where the physical dimensions of the constituent design entities (DEs) can be easily computed in a very short time. A novel high-power compact waffle-iron filter with transmission zeros at multiple frequencies has been designed as well as several classical waffle-iron filters with transmission zeros at one frequency only, using a detailed step-by-step procedure which avoids the bruteforce optimizations needed until now. Multipactor and corona simulations have been conducted proving a high-power handling capability of 1.8 kW and 78.6 W, respectively. A prototype of the novel filter has been fabricated, obtaining a remarkable accordance between the simulated and measured results.
Open Access
Caracterización de composites magneto-dieléctricos usando sensores resonantes de microondas y redes neuronales
(Universidad de Castilla La Mancha, 2024) Álvarez Botero, Germán Andrés; Lobato-Morales, Humberto; Hui, Katherine; Tarabay, Naji; Sánchez-Vargas, Jeu; Méndez-Jerónimo, Gabriela; Pons Abenza, Alejandro; Arregui Padilla, Iván; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Vélez, Camilo; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua
In this paper, we introduce an innovative approach for determining the complex permittivity (ε) and permeability (𝜇)) of magnetodielectric composites. Our methodology uses artificial neural network (ANN) modeling to determine these key parameters from S-parameter data collected at 2.45 GHz. These measurements are performed by a novel microstrip split ring resonator (SRR)-based resonant sensor, offering enhanced precision and reliability in the estimation process.
Open Access
Integración de múltiples stubs en filtros de saltos de impedancias de alta selectividad
(URSI, 2023) Gómez Laso, Miguel Ángel; Sami, Abdul; Lopetegui Beregaña, José María; Martín Iglesias, Petronilo; Álvarez Botero, Germán Andrés; Pons Abenza, Alejandro; Arregui Padilla, Iván; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
Rectangular waveguide commensurate-line stepped-impedance bandpass filters have been shown to have an increased fabrication robustness using conventional CNC milling. In this paper, their frequency response is improved by adding multiple transmission zeros at fully-controlled positions around the passband. The technique starts with the design of the filter without transmission zeros and only requires that one of the filter sections is slightly redesigned, while the rest keep unaltered, when lambda_g/¿¿ and 3*lambda_g/¿¿ stubs are included in the section to increase the overall filter selectivity around the passband. The design example is a 7th-order Chebyshev bandpass filter in Ku-band.
Open Access
Synthesis of one dimensional electromagnetic bandgap structures with fully controlled parameters
(IEEE, 2017) Arnedo Gil, Israel; Chudzik, Magdalena; Percaz Ciriza, Jon Mikel; Arregui Padilla, Iván; Teberio Berdún, Fernando; Benito Pertusa, David; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, we propose a novel synthesis strategy for the design of one dimensional electromagnetic bandgap (1- D-EBG) structures where all the performance parameters of these devices can fully be controlled, i.e., the central frequency of the forbidden band, its attenuation level and bandwidth, and the ripple level at the passbands. The novel synthesis strategy employs a new inverse-scattering technique to accurately synthesize the 1-D-EBG structure, targeting a properly interpolated version of a classical periodic filter fulfilling the required frequency specifications. The new inverse-scattering technique follows a continuous layer peeling approach and relies on the coupled-mode theory to precisely model the microwave structures. Telecommunication and radar systems, as well as material characterization devices, will be profited by this proposal with which enhanced filters, sensors, power dividers, couplers, mixers, oscillators, and amplifiers can be designed in many different technologies. As a proof of concept, a 1-D-EBG structure in microstrip technology with a single forbidden band (free of spurious stopband replicas), with attenuation level of 30 dB, fractional bandwidth larger than 100%, and return loss level at the passbands of 20 dB, has been designed and fabricated. The measurements obtained are in very good agreement with the simulations and target specifications, being free of spurious replicas up to the 15th harmonic, showing the robustness and very good performance of the novel design strategy proposed.
Open Access
Filtro paso banda en tecnología groove gap waveguide con altura de pines reducida para facilitar su fabricación
(Universidad de Málaga, 2022) Santiago Arriazu, David; Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Arregui Padilla, Iván; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In this work, a novel topology of groove gap waveguide (GGW) technology is presented to facilitate the fabrication process by Computer Numerical Control (CNC) milling. GGW has been proposed as an interesting alternative to the rectangular waveguide for the design of microwave and millimeter-wave components. This technology consists of two parallel metal plates, where one of them has a (lambda)/4-height pin bed that provides a high impedance condition at the plane over the pins, avoiding electrical contact requirement with the upper plate and hence facilitating the fabrication requirements. However, the manufacture by CNC milling of the pins may be troublesome, especially for devices operating at high frequency. A way to facilitate this process is achieved by using pins with reduced height. Moreover, the proposed configuration allows us to maintain the standard dimension ports of the equivalent rectangular waveguide and the operation in its corresponding bandwidth. A comparison with other GGW topologies has been presented and a bandpass filter has been fabricated to validate its usefulness.