Open Access
Planar magnetoinductive wave transducers: theory and applications
(AIP Publishing, 2004) Freire, M. J.; Marqués, R.; Medina, Francisco; Gómez Laso, Miguel Ángel; Martín, F.; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Transduction of magnetoinductive waves (MIWs) in planar technology is demonstrated. A transducer consisting of a one-dimensional periodic array of metallic split squared ring resonators (SSRR), placed between a pair of microstrip lines on a planar substrate has been fabricated and measured. The microstrip lines are inductively coupled to the SSRRs located at the ends of the periodic array and excite MIWs that propagate along the array. The theoretical model for the dispersion of MIWs is used to predict the dispersion relation and the delay time in the device. The delay time was measured and a good agreement was found with the theoretical predictions. The transmission coefficient of the device was also measured. The theoretical and experimental results suggest that the proposed configuration can find application in the design of delay lines and other microwave devices. In fact, the behavior of the proposed transducer is similar to that of the conventional ferrite magnetostatic-wave transducer. However, ferrite devices are fragile, difficult to integrate, and require a heavy external magnet or electromagnet to magnetize the ferrite to saturation. Since all these drawbacks are not present in the proposed configuration, it may be a useful alternative to those devices for many practical applications.
Open Access
Filtro de cavidades apiladas en tecnología CLAF-SIW para ondas milimétricas
(Universidad de Castilla-La Mancha, 2024) Segura-Gómez, Cleofás; Biedma-Pérez, Andrés; Santiago Arriazu, David; Palomares-Caballero, Ángel; Arregui Padilla, Iván; Gómez Laso, Miguel Ángel; Padilla, Pablo; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
Este trabajo presenta la validación de la tecnología CLAF-SIW para la fabricación de filtros en el rango de frecuencias de ondas milimétricas. El filtro estudiado es un filtro paso banda compuesto por cuatro cavidades apiladas y acopladas mediante iris (se utilizan cinco iris en total). Cada capa está compuesta por una placa de circuito impreso (PCB) de espesor comercial. Las capas de iris se prototipan metalizando los bordes de las ranuras, mientras que las capas de cavidad contienen la estructura CLAF-SIW utilizando setas dobles como estructura EBG. El filtro se obtiene inmediatamente simplemente adaptando el ancho efectivo de la cavidad CLAF-SIW a la cavidad de referencia, para la cual se han estudiado los efectos que afectan a este valor efectivo. Se ha fabricado un prototipo con buena concordancia entre la medición, la simulación y la respuesta ideal del filtro de cavidad para una banda de paso de 36 a 37,5 GHz. Las pequeñas discrepancias se deben a las diferencias en la separación real entre los laminados y las tolerancias de fabricación.
Open Access
Assessment of performance of one-turn inductors in series configuration through a transmission-line modeling approach
(IEEE , 2024) Álvarez Botero, Germán Andrés; Moctezuma-Pascual, Eduardo; Gómez Laso, Miguel Ángel; Torres-Torres, Reydezel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza
In this paper, transmission-line theory is applied to implement a physical model for compact one-turn inductors, which simultaneously incorporates the frequency-dependent effects introduced by the conductor skin effect and the loss originated by the coupling with the ground plane. For this purpose, S-parameter measurements are processed to extract the associated parameters, which exhibit scalability with the turn radius. This allows the model to be used for interpolation and extrapolation analyses. In this regard, the device performance is assessed for one-turn inductors in series connection, for different load impedances, and when the turn is narrowed. To validate the proposal, agreement between the model and the experimental transmission line RLGC parameters, the return loss, and the Q-factor is obtained up to 20 GHz.
Open Access
Arrangements of via-holes in microstrip lines as metallodielectric periodic structures
(Wiley, 2000) Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Bacaicoa, Miguel; Hernández, Jorge; Gonzalo García, Ramón; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
In this paper, the use of via holes in microstrip lines to design periodic structures that can be regarded as metallodielectric electromagnetic crystals is analyzed. The proposed novel periodic structures achieve a notably increased reflectivity compared to that obtained with a single via hole. Theoretical analysis and experimental results are provided showing a satisfactory performance for these devices as broadband reflectors or short circuits with enhanced behavior at high frequencies.
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.
Open Access
Multipactor breakdown analysis of Ku-band meandered low-pass filter
(2022) Sami, Abdul; Teberio Berdún, Fernando; Arnedo Gil, Israel; Martín Iglesias, Petronilo; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Arregui Padilla, Iván; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
In this work, a very compact rectangular waveguide low-pass filter with meandered topology based on commensurate lines for Ku-band satellite applications is analysed for high-power handling capabilities. The device consists of rectangular waveguide sections properly cascaded to form a meandered topology to obtain the desired value of the local reflection coefficients. which are essential to achieve the target frequency response and also to keep large mechanical gaps. Hence, this technique allows us not only to design a filter with compact size but a filter geometry which is suitable for high power applications. In the paper, the low-pass filter based on commensurate lines is first designed by cascading E-plane mitered bends (±90° EMBs) in CST Microwave Studio (MWS) and then the values of the electromagnetic fields at the passband frequencies are exported to Spark3D to perform a multipactor analysis. The critical areas inside the device where the multipactor discharge occurs will also be identified in the high-power analysis. https://doi.org/10.5281/zenodo.7343236
Open Access
Synthesis of rectangular waveguide filters with smooth profile oriented to direct metal additive manufacturing
(IEEE, 2023) Percaz Ciriza, Jon Mikel; Hussain, Jabir; Arregui Padilla, Iván; Teberio Berdún, Fernando; Benito Pertusa, David; Martín Iglesias, Petronilo; Arnedo Gil, Israel; Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In this paper, a novel design method for rectangular waveguide filters intended for fabrication using direct metal additive manufacturing is proposed. The synthesized filters will feature a smooth profile that allows us to fabricate them orienting the filter propagation axis in the vertical building direction, achieving an optimum configuration for direct metal additive manufacturing fabrication. The novel design method is valid for any all-pole transfer function, which is initially implemented with a commensurate-line distributed unit element prototype. The impulse response of that initial prototype is then properly interpolated to obtain the target response for a smooth-profiled filter with similar length and profile excursion. Finally, the target impulse response just generated is implemented in rectangular waveguide technology employing a novel inverse scattering synthesis technique that relies on the coupled-mode theory to model the electromagnetic behavior of the waveguide filter. The novel inverse scattering synthesis technique is general and also valid for the case of filters with very high rejection levels, which is of great relevance in rectangular waveguide technology. A Ku-band low-pass filter with stringent satellite specifications is designed using the proposed method, fabricated by means of a direct metal additive manufacturing technique, and measured with a vector network analyzer. A very good agreement is achieved between the simulated and measured results, fulfilling the required specifications and demonstrating the feasibility and performance of the novel design method.
Open Access
Chirping techniques to maximize the power-handling capability of harmonic waveguide low-pass filters
(IEEE, 2016) Teberio Berdún, Fernando; Arregui Padilla, Iván; Gómez Torrent, Adrián; Arnedo Gil, Israel; Chudzik, Magdalena; Zedler, Michael; Goertz, Franz-Josef; Jost, Rolf; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A novel chirping technique is applied to the design of very high-power waveguide harmonic low-pass filters. The technique could be used, for instance, to avoid multipactor testing in multicarrier systems such as the output multiplexer of a communications satellite. The novel chirped filter shows low insertion loss, all higher order mode suppression, and broad stopband rejection up to the third harmonic. This paper focuses on the maximization of the filter power-handling capability without affecting its excellent frequency behavior. Given a certain frequency response, the E-plane mechanical gap of the structure and the length (in the propagation direction) of the waveguide sections between its constituent bandstop elements can be considered to improve the high-power behavior. However, the power performance may not be sufficient yet in some applications if we wish, for instance, multipactor testing to be avoided. This becomes feasible by chirping the length (in the propagation direction) of the bandstop elements. An example for Ku band is discussed for relevant frequency specifications. An improvement from ∼8 kW (non-chirped filter) to more than 100 kW (chirped filter) is obtained. As a reference, the equivalent waffle-iron filter can handle only 0.15 kW. Such high-power threshold levels have never been reported before for such kind of filters.
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
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.