Efficient methods for radiation, scattering and propagation. Poster

This document describes the research activities performed in the areas of antennas, scattering and wave propagation by several research groups belonging to different Universities located in Eastern Spain. These groups are working in the practical applications of efficient numerical electromagnetic methods within the frame of several research projects funded by private and public Spanish and European institutions. The main results obtained by these groups related to such topics, i.e. analysis algorithms, CAD tools, validation prototypes, as well as most relevant publications in technical conferences, journals and books, will be thoroughly described in this summary

Propagation Characteristics of Groove Gap Waveguide Below and Above Cutoff

(c) 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.Recently, gap waveguides have been shown as a potential alternative to convenational waveguides in the millimeter-wave band. Until now, groove gap waveguide (GGW) has been studied through direct correspondence with rectangular waveguide with the same physical dimensions. However, there have been observed differences in the above cutoff propagation characteristics between these two waveguide types. Furthermore, the behavior of GGW below cutoff remains unknown. This work presents a discussion of both below and above cutoff propagation characteristics of GGW, and introduces a simple model that explains the observed GGW behavior and establishes well its propagation characteristics. Two thru-reflect-line calibration kits have been manufactured, and the measurements have good agreement with the proposed analysis model results.This work was supported by the Spanish Ministerio de Economia y Competitividad under Project TEC2013-47360-C3-3-P and Project TEC2013-47037-C5-1-R and by the Spanish Ministerio de Educacion under FPU Research Fellowship Program AP2010-4227.Berenguer Verdú, AJ.; Fusco, V.; Zelenchuk, DE.; Sánchez-Escuderos, D.; Baquero Escudero, M.; Boria Esbert, VE. (2016). Propagation Characteristics of Groove Gap Waveguide Below and Above Cutoff. IEEE Transactions on Microwave Theory and Techniques. 64(1):27-36. https://doi.org/10.1109/TMTT.2015.2504501S273664

Multipactor radiation analysis within a waveguide region based on a frequency-domain representation of the dynamics of charged particles

[EN] A technique for the accurate computation of the electromagnetic fields radiated by a charged particle moving within a parallel-plate waveguide is presented. Based on a transformation of the time-varying current density of the particle into a time-harmonic current density, this technique allows the evaluation of the radiated electromagnetic fields both in the frequency and time domains, as well as in the near- and far-field regions. For this purpose, several accelerated versions of the parallel-plate Green's function in the frequency domain have been considered. The theory has been successfully applied to the multipactor discharge occurring within a two metal-plates region. The proposed formulation has been tested with a particle-in-cell code based on the finite-difference time-domain method, obtaining good agreement.The authors would like to thank ESA/ESTEC for having funded this research activity through the Contract "RF Breakdown in Multicarrier Systems" (Contract No. 19918/06/NL/GLC).Gimeno, B.; Sorolla, E.; Anza, S.; Vicente, C.; Gil, J.; Pérez, AM.; Boria Esbert, VE.... (2009). Multipactor radiation analysis within a waveguide region based on a frequency-domain representation of the dynamics of charged particles. Physical review. E, Statistical, nonlinear, and soft matter physics. 79(4):1-9. https://doi.org/10.1103/PhysRevE.79.046604S19794Figueroa, H., Gai, W., Konecny, R., Norem, J., Ruggiero, A., Schoessow, P., & Simpson, J. (1988). Direct Measurement of Beam-Induced Fields in Accelerating Structures. Physical Review Letters, 60(21), 2144-2147. doi:10.1103/physrevlett.60.2144Ng, K.-Y. (1990). Wake fields in a dielectric-lined waveguide. Physical Review D, 42(5), 1819-1828. doi:10.1103/physrevd.42.1819Rosing, M., & Gai, W. (1990). Longitudinal- and transverse-wake-field effects in dielectric structures. Physical Review D, 42(5), 1829-1834. doi:10.1103/physrevd.42.1829Gai, W., Kanareykin, A. D., Kustov, A. L., & Simpson, J. (1997). Numerical simulations of intense charged-particle beam propagation in a dielectric wake-field accelerator. Physical Review E, 55(3), 3481-3488. doi:10.1103/physreve.55.3481Burov, A., & Danilov, V. (1999). Suppression of Transverse Bunch Instabilities by Asymmetries in the Chamber Geometry. Physical Review Letters, 82(11), 2286-2289. doi:10.1103/physrevlett.82.2286Xiao, L., Gai, W., & Sun, X. (2001). Field analysis of a dielectric-loaded rectangular waveguide accelerating structure. Physical Review E, 65(1). doi:10.1103/physreve.65.016505Jing, C., Liu, W., Xiao, L., Gai, W., Schoessow, P., & Wong, T. (2003). Dipole-mode wakefields in dielectric-loaded rectangular waveguide accelerating structures. Physical Review E, 68(1). doi:10.1103/physreve.68.016502Stupakov, G., Bane, K. L. F., & Zagorodnov, I. (2007). Optical approximation in the theory of geometric impedance. Physical Review Special Topics - Accelerators and Beams, 10(5). doi:10.1103/physrevstab.10.054401Hatch, A. J., & Williams, H. B. (1954). The Secondary Electron Resonance Mechanism of Low‐Pressure High‐Frequency Gas Breakdown. Journal of Applied Physics, 25(4), 417-423. doi:10.1063/1.1721656Hatch, A. J., & Williams, H. B. (1958). Multipacting Modes of High-Frequency Gaseous Breakdown. Physical Review, 112(3), 681-685. doi:10.1103/physrev.112.681Vaughan, J. R. M. (1988). Multipactor. IEEE Transactions on Electron Devices, 35(7), 1172-1180. doi:10.1109/16.3387Gilardini, A. L. (1995). Multipacting discharges: Constant‐ktheory and simulation results. Journal of Applied Physics, 78(2), 783-795. doi:10.1063/1.360336Riyopoulos, S. (1997). Multipactor saturation due to space-charge-induced debunching. Physics of Plasmas, 4(5), 1448-1462. doi:10.1063/1.872319Kryazhev, A., Buyanova, M., Semenov, V., Anderson, D., Lisak, M., Puech, J., … Sombrin, J. (2002). Hybrid resonant modes of two-sided multipactor and transition to the polyphase regime. Physics of Plasmas, 9(11), 4736-4743. doi:10.1063/1.1514969Udiljak, R., Anderson, D., Ingvarson, P., Jordan, U., Jostell, U., Lapierre, L., … Sombrin, J. (2003). New method for detection of multipaction. IEEE Transactions on Plasma Science, 31(3), 396-404. doi:10.1109/tps.2003.811646De Lara, J., Perez, F., Alfonseca, M., Galan, L., Montero, I., Roman, E., & Garcia-Baquero, D. R. (2006). Multipactor prediction for on-board spacecraft RF equipment with the MEST software tool. IEEE Transactions on Plasma Science, 34(2), 476-484. doi:10.1109/tps.2006.872450Torregrosa, G., Coves, A., Vicente, C. P., Perez, A. M., Gimeno, B., & Boria, V. E. (2006). Time evolution of an electron discharge in a parallel-plate dielectric-loaded waveguide. IEEE Electron Device Letters, 27(7), 619-621. doi:10.1109/led.2006.877284Udiljak, R., Anderson, D., Lisak, M., Semenov, V. E., & Puech, J. (2007). Multipactor in a coaxial transmission line. I. Analytical study. Physics of Plasmas, 14(3), 033508. doi:10.1063/1.2710464Semenov, V. E., Zharova, N., Udiljak, R., Anderson, D., Lisak, M., & Puech, J. (2007). Multipactor in a coaxial transmission line. II. Particle-in-cell simulations. Physics of Plasmas, 14(3), 033509. doi:10.1063/1.2710466Anza, S., Vicente, C., Gimeno, B., Boria, V. E., & Armendáriz, J. (2007). Long-term multipactor discharge in multicarrier systems. Physics of Plasmas, 14(8), 082112. doi:10.1063/1.2768019Udiljak, R., Anderson, D., Lisak, M., Puech, J., & Semenov, V. E. (2007). Multipactor in a Waveguide Iris. IEEE Transactions on Plasma Science, 35(2), 388-395. doi:10.1109/tps.2007.892737Burton, R. J., de Jong, M. S., & Funk, L. W. (1991). Vacuum and multipactor performance of the hadron electron ring accelerator 52 MHz cavities. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 9(3), 2081-2084. doi:10.1116/1.577417Yamaguchi, S., Saito, Y., Anami, S., & Michizono, S. (1992). Trajectory simulation of multipactoring electrons in an S-band pillbox RF window. IEEE Transactions on Nuclear Science, 39(2), 278-282. doi:10.1109/23.277497Kishek, R., & Lau, Y. Y. (1995). Interaction of Multipactor Discharge and rf Circuit. Physical Review Letters, 75(6), 1218-1221. doi:10.1103/physrevlett.75.1218Lay-Kee Ang, Lau, Y. Y., Kishek, R. A., & Gilgenbach, R. M. (1998). Power deposited on a dielectric by multipactor. IEEE Transactions on Plasma Science, 26(3), 290-295. doi:10.1109/27.700756Kishek, R. A., Lau, Y. Y., Ang, L. K., Valfells, A., & Gilgenbach, R. M. (1998). Multipactor discharge on metals and dielectrics: Historical review and recent theories. Physics of Plasmas, 5(5), 2120-2126. doi:10.1063/1.872883Neuber, A., Hemmert, D., Krompholz, H., Hatfield, L., & Kristiansen, M. (1999). Initiation of high power microwave dielectric interface breakdown. Journal of Applied Physics, 86(3), 1724-1728. doi:10.1063/1.370953Chojnacki, E. (2000). Simulations of a multipactor-inhibited waveguide geometry. Physical Review Special Topics - Accelerators and Beams, 3(3). doi:10.1103/physrevstab.3.032001Cimino, R., Collins, I. R., Furman, M. A., Pivi, M., Ruggiero, F., Rumolo, G., & Zimmermann, F. (2004). Can Low-Energy Electrons Affect High-Energy Physics Accelerators? Physical Review Letters, 93(1). doi:10.1103/physrevlett.93.014801Abe, T., Kageyama, T., Akai, K., Ebihara, K., Sakai, H., & Takeuchi, Y. (2006). Multipactoring zone map of an rf input coupler and its application to high beam current storage rings. Physical Review Special Topics - Accelerators and Beams, 9(6). doi:10.1103/physrevstab.9.062002Sorolla, E., Anza, S., Gimeno, B., Perez, A. M. P., Vicente, C., Gil, J., … Boria, V. E. (2008). An Analytical Model to Evaluate the Radiated Power Spectrum of a Multipactor Discharge in a Parallel-Plate Region. IEEE Transactions on Electron Devices, 55(8), 2252-2258. doi:10.1109/ted.2008.926271Harrington, R. F. (2001). Time-Harmonic Electromagnetic Fields. doi:10.1109/9780470546710Hanson, G. W., & Yakovlev, A. B. (2002). Operator Theory for Electromagnetics. doi:10.1007/978-1-4757-3679-3Ewald, P. P. (1921). Die Berechnung optischer und elektrostatischer Gitterpotentiale. Annalen der Physik, 369(3), 253-287. doi:10.1002/andp.19213690304Myun-Joo Park, & Sangwook Nam. (1998). Rapid summation of the Green’s function for the rectangular waveguide. IEEE Transactions on Microwave Theory and Techniques, 46(12), 2164-2166. doi:10.1109/22.739301Capolino, F., Wilton, D. R., & Johnson, W. A. (2005). Efficient computation of the 2-D Green’s function for 1-D periodic structures using the Ewald method. IEEE Transactions on Antennas and Propagation, 53(9), 2977-2984. doi:10.1109/tap.2005.854556Kustepeli, A., & Martin, A. Q. (2000). On the splitting parameter in the Ewald method. IEEE Microwave and Guided Wave Letters, 10(5), 168-170. doi:10.1109/75.85036

Dispersión de objetos 2D dieléctricos y magnéticos usando bases wavelet

Lossy dielectric and magnetic obstacles are typically present in many high-frequency scattering applications. In this paper, we study this problem using the Equivalence Principle and the Method of Moments (MoM). When the structure is complex and high accuracy is required, the number of unknowns in the numerical solution naturally grows. Therefore, we propose the use of wavelet-like bases to improve the numerical efficiency and memory requirements. For verification purposes, the results provided by the new technique are successfully compared with those obtained with the conventional MoM approach. The new technique has been applied to characterize the scattering behavior of large square and elliptical obstacles, as well as multilayer structures, which are composed of lossy homogeneous media and conductors.Este trabajo ha sido financiado por el Ministerio de Educación y Ciencia, bajo los proyectos de investigación TEC2004/04313-C02-01, TEC2004/04313-C02-02, y el proyecto de la fundación Séneca PB/4/FS/02

Efficient analysis of arbitrarily shaped inductive obstacles in rectangular waveguides using a surface integral equation formulation

In this paper we propose to use the Surface Integral Equation technique for the analysis of arbitrarily shaped Hplane obstacles in rectangular waveguides, which can contain both metallic and/or dielectric objects. The Green functions are formulated using both spectral and spatial images series, whose convergence behavior has been improved through several acceleration techniques. Proceeding in this way, the convergence of the series is not attached to the employment of any particular basis or test function, thus consequently increasing the flexibility of the implemented technique. In order to test the accuracy and numerical efficiency of the proposed method, results for practical microwave circuits have been successfully compared with other numerical approaches.The authors would like to thank Alcatel Alenia Space (Madrid, Spain) for having provided data of the lossy dielectric loaded evanescent waveguide filter. They also wish to acknowledge the economic support of MEC, Spanish Government, through the coordinated Research Project TEC2004/04313-C02

Propagation Characteristics of Groove Gap Waveguide Below and Above Cutoff

Recently, gap waveguides have been shown as a potential alternative to conventional waveguides in the millimeterwave band. Until now, Groove Gap Waveguide (GGW) has been studied through direct correspondence with rectangular waveguide with the same physical dimensions. However there have been observed differences in the above cutoff propagation characteristics between these two waveguide types. Furthermore, the behavior of GGW below cutoff remains unknown. This work presents a discussion of both below and above cutoff propagation characteristics of GGW, and introduces a simple model that explains the observed GGW behavior and establishes well its propagation characteristics. Two TRL calibration kits have been manufactured, and the measurements have good agreement with the proposed analysis model results

Estudio del fenómeno multipactor en componentes pasivos inductivos de microondas para aplicaciones espaciales

En este artículo se investiga el riesgo de multipactor en filtros inductivos de microondas en guía. Para el estudio, se ha utilizado una herramienta software basada en una formulación de ecuación integral de superficie. La precisión y la eficiencia del método empleado ha permitido por primera vez predecir el riesgo de multipactor en dispositivos en guía inductivos complejos, incluyendo filtros dieléctricos de cavidad cargados y filtros en guía evanescente acoplados con resonadores dieléctricos. El estudio revela un riesgo más alto de multipactor en filtros con un ancho de banda más estrecho. Para reducir el problema asociado a la generación de multipactor, se propone una nueva estructura de filtro inductivo. Los resultados indican que con ésta que se puede disminuir el riesgo hasta un 30% en relación al diseño inicial

Analysis of multipactor effect using a phase-shift keying single-carrier digital modulated signal

The main aim of this paper is the analysis of the multipactor effect within a coaxial waveguide structure excited by a phase-shift keying single-carrier digital modulated signal. To reach this aim, we developed in-house a software code which is able to predict the RF multipactor input voltage threshold. This code is based on the single effective electron model, and considers the space charge effect. Numerical simulations are performed for binary phase-shift keying and quadrature phase-shift keying modulated signals. In addition, an experiment is carried out to validate the proposed theoretical model. We have demonstrated that the digital modulation of the single-carrier signal may modify the RF voltage threshold in comparison to the nonmodulated scenario. Good agreement between theory and experimental data is found.Gonzalez Iglesias, D.; Belloch Rodríguez, MP.; Monerris Belda, Ó.; Gimeno Martinez, B.; Boria Esbert, VE.; Raboso García-Baquero, D.; Semenov, VE. (2013). Analysis of multipactor effect using a phase-shift keying single-carrier digital modulated signal. IEEE Transactions on Electron Devices. 60(8):2664-2670. doi:10.1109/TED.2013.2266275S2664267060

Efficient analysis of inductive multiport waveguide circuits using a surface integral equation formulation

This paper presents a simple and alternative approach for the analysis of inductive multiport waveguide microwave components. The technique uses a surface integral equation formulation to treat both metallic and dielectric objects inside the component structure. In order to avoid the relative convergence problem of other techniques based on mode matching, a novel port treatment is used. The technique is based on the application of the extinction theorem using the spatial representation of the Green's functions and image theory. Different complex H-plane structures are analyzed, including microwave bandpass filters with elliptic transfer functions and waveguide bends with dielectric posts. Results show the high accuracy and versatility of the new technique derive

Análisis eficiente de componentes pasivos inductivos en guía empleando una nueva formulación de ecuación integral en el dominio espacial

En artículo se presenta una herramienta software para el análisis de componentes inductivos en guía de onda, usando una nueva formulación ecuación integral de superficie en el dominio espacial. Por primera vez se combinan diferentes técnicas de aceleración de series en una única formulación, para la evaluación eficiente en el dominio espacial de las funciones de Green de la guía de placas paralelas. Se presentan resultados de filtros de microondas complejos que contienen postes dieléctricos y esquinas redondeadas, pudiéndose comprobar, de este modo, la utilidad y la precisión del método propuesto