Exploring the Tuning Range of Channel Filters for Satellite Applications Using Electromagnetic-Based Computer Aided Design Tools

© 2018 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] The objective of this paper is to use electromagnetic-based computer-aided design (CAD) tools to investigate the maximum tuning range of channel filters, typically used in satellite payloads. Both circular and rectangular waveguide technologies are investigated. The results of the investigation show that single-mode rectangular waveguide implementations offer substantially wider tuning range, as opposed to classical dual-mode circular waveguide implementations. In addition to simulations, measurements are also presented indicating very good agreement with theory, thereby fully validating the CAD procedure.This work was supported in part by MINECO (Spanish Government) under Research and Development Project TEC2016-75934-C4-1-R and in part by Research and Development Technicians under Grant PTA2015-10839-I.Ossorio-García, J.; Vague Cardona, JJ.; Boria Esbert, VE.; Guglielmi, M. (2018). Exploring the Tuning Range of Channel Filters for Satellite Applications Using Electromagnetic-Based Computer Aided Design Tools. IEEE Transactions on Microwave Theory and Techniques. 66(2):717-725. https://doi.org/10.1109/TMTT.2017.2769083S71772566

Substrate Integrated Waveguide Diplexer Based on Circular Triplet Combline Filters

The design of substrate integrated waveguide (SIW) diplexers, based on combline triplet sections with transmission zeros (TZs) placed below and above the passband, is presented. In order to control the location of the TZs, positive and negative couplings are conveniently provided. A highly compact implementation based on circular substrate integrated coaxial resonators is proposed. An X band diplexer with channel center frequencies at 9.5 and 10.5 GHz and absolute bandwidths of 400 MHz is designed. The structure shows important advantages in terms of size reduction, while keeping good insertion losses as well as high rejection and isolation levels.This work was supported by MINECO (Spanish Government) under projects TEC2103-47037-C5-1-R and TEC2013-48036-C3-3-R.Sirci, S.; Martínez Pérez, JD.; Vague Cardona, JJ.; Boria Esbert, VE. (2015). Substrate Integrated Waveguide Diplexer Based on Circular Triplet Combline Filters. IEEE Microwave and Wireless Components Letters. 25(7):430-432. doi:10.1109/LMWC.2015.2427516S43043225

Novel Planar and Waveguide Implementations of Impedance Matching Networks Based on Tapered Lines Using Generalized Superellipses

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] For the practical implementation of RF and microwave impedance matching networks, a widely employed solution¿alternative to the use of classical impedance transformers¿is based on tapered lines. This paper shows a simple method to design smooth tapers that take into account the dispersion of the line and the required design bandwidth simultaneously. A planar taper has been designed in microstrip technology with the same length of classical ones but improving their performances. A waveguide prototype has also been designed with similar performance to a commercial one but with one third of its length. Both tapered structures have been obtained through the optimization of very few parameters using the same design strategy. As a result, the reflection coefficient of the tapers can be optimally adapted to a given specific mask using the prescribed value of physical length. Experimental results for both tapers are included for the validation of the proposed topologies and the related design method.This work was supported by MINECO (Spanish Government) through R&D under Project TEC2016-75934-C4-1-R.Cogollos, S.; Vague Cardona, JJ.; Boria Esbert, VE.; Martínez Pérez, JD. (2018). Novel Planar and Waveguide Implementations of Impedance Matching Networks Based on Tapered Lines Using Generalized Superellipses. IEEE Transactions on Microwave Theory and Techniques. 66(4):1874-1884. https://doi.org/10.1109/TMTT.2018.2791952S1874188466

Optimized Design of Combline Filters with Transmission Zeros

[EN] The objective of this paper is to demonstrate how inline combline filters can be designed to implement transmission zeros in the filter transfer function. Following the design procedure described in this paper, up to N-1 transmission zeros can be implemented with a filter of order N. In addition to theory, comparisons between simulated and measured results are also presented. The agreement between simulation and measurements is indeed good, thereby fully validating the new combline filter topology, and the proposed design technique.Vague Cardona, JJ.; Ossorio García, J.; Cogollos, S.; Boria Esbert, VE.; Guglielmi, M. (2019). Optimized Design of Combline Filters with Transmission Zeros. IEEE. 1-3. https://doi.org/10.1109/NEMO.2019.8853819S1

Study of the Multipactor Effect in Groove Gap Waveguide Technology

[EN] This article presents a theoretical and experimental comparative study of the different multipactor threshold values obtained in the rectangular waveguide (RW) and the groove gap waveguide (GGW). To this end, the multipactor effect has been first analyzed in an RW with a recently developed theoretical model. Then, the multipactor breakdown power levels in the equivalent GGW have been predicted with an accurate electron tracking code, showing a significant increment compared with the RW case. In order to validate these results, two E-plane WR-90 RW transformers have been designed with a full-wave electromagnetic simulation tool. The central sections of these transformers have been implemented in RW and GGW, respectively, and their multipactor breakdown power levels have also been predicted. The two designed transformers have been fabricated in aluminum and then measured in terms of electrical response (scattering parameters) and RF multipactor effect (power threshold values). All the experimental results agree well with the set of simulated data, thus fully validating the performed study.This work was supported by the Ministerio de Ciencia e Innovacion, Spanish Government, through the Subprojects C41 and C43 of the Coordinated Research and Development Project PID2019103982RB under Grant MCIN/AEI/10.13039/501100011033.Vague Cardona, JJ.; Asensio, I.; Coves, Á.; San Blas, ÁA.; Reglero Mangada, MS.; Vidal Pantaleoni, A.; Raboso, D.... (2022). Study of the Multipactor Effect in Groove Gap Waveguide Technology. IEEE Transactions on Microwave Theory and Techniques. 70(5):2566-2578. https://doi.org/10.1109/TMTT.2022.31575872566257870

Multipactor Threshold Estimation Techniques Based on Circuit Models, Electromagnetic Fields and Particle Simulators

[EN] Multipactor has become a keylimiting factor of the final performance of satellite communication systems, due to the increase in power levels and/or operating frequency bands. As a result, the critical components of these systems must meet demanding multipactor specifications which should be considered during the design process. This paper describes the different techniques available to predict the multipactor threshold power for radio frequency (RF) and microwave passive hardware under continuous wave (CW) excitation, from cumbersome particle simulations to fast approximate methods based on circuit models. All these techniques have been described and compared together for the first time, including also a detailed description of the configuration issues of commercial particle simulators required to obtain accurate multipactor threshold predictions. The techniques are applied to both wideband and narrowband application examples. The predictions have been compared with measured thresholds of manufactured samples obtained with a novel multipactor test bed, thus allowing to highlight the advantages and limitations of each technique and particle simulator. From this paper, it will be possible to choose the most suitable procedure (and an appropriate simulator, if needed) to obtain multipactor threshold prediction of passive hardware.The work of Pablo González was supported by the FPU Fellowship of the Ministerio de Educación, Cultura y Deporte, Spanish Government, with Ref. FPU17/02901. This work was supported in part by the Ministerio de Ciencia e Innovación (MICIN, Spanish Government) under R&D Project PID2019-103982RB-C41 (funded by MICIN/AEI/10.13039/501100011033), and in part by the European Space Agency (ESA) under Project H2020-ESA-007 (funded by the European Union's Horizon 2020 Research and Innovation Program).González-Santatecla, P.; Alcaide, C.; Cervera, R.; Rodríguez, M.; Monerris, Ó.; Petit, J.; Rodríguez Pérez, AM.... (2022). Multipactor Threshold Estimation Techniques Based on Circuit Models, Electromagnetic Fields and Particle Simulators. IEEE Journal of Microwaves. 2(1):57-77. https://doi.org/10.1109/JMW.2021.313228457772

Multipactor mitigation in coaxial lines by means of permanent magnets

The main aim of this paper is the analysis of the feasibility of employing permanent magnets for the multipactor mitigation in a coaxial waveguide. First, the study of a coaxial line immersed in a uniform axial magnetic field shows that multipactor can be suppressed at any RF if the external magnetic field is strong enough. Both theoretical simulations and experimental tests validate this statement. Next, multipactor breakdown of a coaxial line immersed in a hollow cylindrical permanent magnet is analyzed. Numerical simulations show that multipactor can be suppressed in a certain RF range. The performed experimental test campaign demonstrates the capability of the magnet to avoid the multipactor electron multiplication process.This work was supported by the European Regional Development Fund-A Way of Making Europe. The review of this paper was arranged by Editor R. Carter.Gonzalez Iglesias, D.; Pérez Pastor, AM.; Anza Hormigo, S.; Vague Cardona, JJ.; Gimeno Martinez, B.; Boria Esbert, VE.; Raboso García-Baquero, D.... (2014). Multipactor mitigation in coaxial lines by means of permanent magnets. IEEE Transactions on Electron Devices. 61(12):4224-4231. doi:10.1109/TED.2014.2361172S42244231611

Multipactor Effect Characterization of Dielectric Materials for Space Applications

[EN] The objective of this paper is to advance the state of the art in the characterization of the multipactor effect in dielectric materials. The materials studied are the most commonly used dielectrics in space applications, namely, Alumina, Rexolite, Rogers RT5870, Rohacell, Teflon, and Ultem 1000. In this paper, a new family of coaxial waveguide components, covering the L- and S-bands, with a wideband, low-pass response has been designed, and six different prototypes have been specifically optimized and manufactured. The six prototypes have then been used to simulate and measure the multipactor breakdown susceptibility charts for the six dielectric materials investigated. Finally, the simulation results are compared with the results of the measurement campaign indicating good agreement.This work was supported in part by the European Space Agency through Research Project "Novel Investigation in Multipactor Effect in Ferrite and Other Dielectrics Used in High Power RF Space Hardware" under Grant AO 1-7551/13/NL/GLC and in part by MINECO (Spanish Government) through Research and Development Project under Grant TEC2016-75934-C4-1-R. This paper is an expanded version from the IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes IMWS-AMP 2017, Pavia, Italy, September 20-22, 2017.Vague Cardona, JJ.; Melgarejo-Lermas, JC.; Guglielmi, M.; Boria Esbert, VE.; Anza Hormigo, S.; Vicente Quiles, CP.; Moreno Cambroreno, MDR.... (2018). Multipactor Effect Characterization of Dielectric Materials for Space Applications. IEEE Transactions on Microwave Theory and Techniques. 66(8):3644-3655. https://doi.org/10.1109/TMTT.2018.2845869S3644365566

Experimental validation of multipactor effect for ferrite materials used in L- and S-band nonreciprocal microwave components

This paper reports on the experimental measurement of power threshold levels for the multipactor effect between samples of ferrite material typically used in the practical implementation of L- and S-band circulators and isolators. For this purposes, a new family of wideband, nonreciprocal rectangular waveguide structures loaded with ferrites has been designed with a full-wave electromagnetic simulation tool. The design also includes the required magnetostatic field biasing circuits. The multipactor breakdown power levels have also been predicted with an accurate electron tracking code using measured values for the secondary electron yield (SEY) coefficient. The measured results agree well with simulations, thereby fully validating the experimental campaign.This work was supported by European Space Agency (ESA) through research project "Novel Investigation in Multipactor Effect in Ferrite and other Dielectrics used in High Power RF Space Hardware" (ref. AO 1-7551/13/NL/GLC), and by MINECO (Spanish Government) under R&D projects TEC2016-75934-C4-1-R, TEC2016-75934-C4-2-R and the ERDF co-funded project TEC2014-55463-C3-3-P

Enhanced Grid Fundamental Positive-Sequence Digital Synchronization Structure

The second-order generalized integrator (SOGI) filter and delayed signal cancellation (DSC) structures have been used separately in order to improve the synchronization systems response in adverse grid conditions. Taking into account its characteristics, this paper proposes a new structure based on a combination of SOGI filter, DSC method, and a software phase-locked loop (S). The enhanced synchronization structure is used to estimate the fundamental positive-sequence component of grid voltages (v(s1)(+)) in distorted and asymmetric three-phase systems. DSC and SOGI working in the stationary alpha-beta frame are used to obtain the v(s1)(+) component, while S in a synchronous reference frame (SRF) or the d-q frame is used to obtain v(s1)(+) pulsation and phase. The cutting frequency of the SOGI filter is selected by taking into account the capability of DSC to eliminate determinate order harmonic components. The bandwidth of S is adjusted to achieve a good relation between dynamic response and filtering capability. The SOGI filter has an adaptive structure to modify its cutting frequency when a variation in the fundamental frequency of grid voltages occurs. The performance of the proposed structure is verified through simulations and experimental cases, using a grid set of voltages that include all nonefficient voltage components (distortion, asymmetries, and negative-sequence components).Alfonso Gil, JC.; Vague Cardona, JJ.; Orts-Grau, S.; Gimeno Sales, FJ.; Segui-Chilet, S. (2013). Enhanced Grid Fundamental Positive-Sequence Digital Synchronization Structure. IEEE Transactions on Power Delivery. 28(1):226-234. doi:10.1109/TPWRD.2012.2219559S22623428