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(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] This paper provides the guidelines for the practical development of novel advanced test beds for passive intermodulation(PIM) measurements. The proposed test beds show high performance and are flexible, allowing for the measurement of several PIM signals of different orders, with two or more input carriers. In contrast to classic test beds for satellite hardware, based on the cascaded connection of several elements, an integrated solution involving the minimum number of hardware pieces is proposed. The result is a lower number of flanged interconnections, thus reducing residual PIM level and insertion losses. In addition, return loss degradation and harmful spurious generation in the interconnections are also avoided. Measurement test beds for conducted and radiated PIM, in both transmitted and reflected directions, are discussed, highlighting the benefits and drawbacks of each configuration. Design guidelines for the key components are fully discussed. Illustrative application examples are also reported. Finally, excellent experimental results obtained from low-PIM measurement setups, working from C-band to Ka-band, are shown, thus fully confirming the validity of the proposed configurations. ; This work was supported in part by the European Space Agency through several research and development contracts, in part by the Ministerio de Economia y Competitividad (Spanish Government) under Project TEC2016-75934-C4-1-R, and in part by the ESA-VSC High Power RF Space Laboratory. ; Smacchia, D.; Soto Pacheco, P.; Boria Esbert, VE.; Guglielmi, M.; Carceller Candau, C.; Ruiz-Garnica, J.; Galdeano, J. (2018). Advanced Compact Setups for Passive Intermodulation Measurements of Satellite Hardware. IEEE Transactions on Microwave Theory and Techniques. 66(2):700-710. https://doi.org/10.1109/TMTT.2017.2783383 ; S ; 700 ; 710 ; 66 ; 2

A technique for the accurate computation of the time domain electromagnetic fields radiated by a charged distribution traveling along an arbitrarily shaped waveguide region is presented. Based on the transformation (by means of the standard Fourier analysis) of the time-varying current density of the analyzed problem to the frequency domain, the resulting equivalent current is further convolved with the dyadic electric and magnetic Green's functions. Moreover, we show that only the evaluation of the transverse magnetic modes of the structure is required for the calculation of fields radiated by particles traveling in the axial direction. Finally, frequency domain electric and magnetic fields are transformed back to the time domain, just obtaining the total fields radiated by the charged distribution. Furthermore, we present a method for the computation of the wakefields of arbitrary cross-section uniform waveguides from the resulting field expressions. Several examples of charged particles moving in the axial direction of such waveguides are included. ; The authors would like to thank ESA/ESTEC for having cofunded this research activity through the Network Partnering Initiative program and through the project "Multipactor Analysis in Planar Transmission Lines" (contract 20841/08/NL/GLC). We also are grateful to the Spanish government and the local Council of Murcia for their support through the projects CICYT Ref. TEC2010-21520-C04-04 and SENECA Ref. 08833/PI/08, respectively. ; Jimenez Nogales, M.; Marini, S.; Gimeno Martinez, B.; Alvarez Melcon, A.; Quesada Pereira, FD.; Boria Esbert, VE.; Soto Pacheco, P. (2012). Evaluation of time domain electromagnetic fields radiated by constant velocity moving particles traveling along an arbitrarily shaped cross-section waveguide using frequency domain Green's functions. Radio Science. 47(5):1-14. https://doi.org/10.1029/2012RS005008 ; S ; 1 ; 14 ; 47 ; 5 ; Alvarez-Melcon, A., & Mosig, J. R. (2000). Two techniques for the efficient numerical calculation of the ...

[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.2018.2845869 ; S ; 3644 ; 3655 ; 66 ; 8

In this paper, the multipactor RF breakdown in a parallel-plate waveguide partially filled with a ferrite slab magnetized normal to the metallic plates is studied. An external magnetic field is applied along the vertical direction between the plates in order to magnetize the ferrite. Numerical simulations using an in-house 3-D code are carried out to obtain the multipactor RF voltage threshold in this kind of structures. The presented results show that the multipactor RF voltage threshold at certain frequencies becomes considerably lower than for the corresponding classical metallic parallel-plate waveguide with the same vacuum gap ; This work was supported in part by the European Space Agency under Novel Investigation in Multipactor Effect in Ferrite and other Dielectrics used in high power RF Space Hardware under Contract AO 1-7551/13/NL/GLC, in part by the Spanish Government under Coordinated R&D Project TEC2013- 47037-5-R and Project TEC2014-55463-C3-3-P, and in part by the European Commission (ERDF). The review of this paper was arranged by Editor R. Carter. ; Gonzalez Iglesias, D.; Gomez, A.; Gimeno Martinez, B.; Fernández, O.; Vegas, A.; Casas, F.; Anza Hormigo, S. (2016). Analysis of Multipactor RF Breakdown in a Waveguide Containing a Transversely Magnetized Ferrite. IEEE Transactions on Electron Devices. 63(12):4939-4947. doi:10.1109/TED.2016.2614370 ; S ; 4939 ; 4947 ; 63 ; 12

In this paper, the multipactor RF breakdown in a parallel-plate waveguide partially filled with a ferrite slab magnetized normal to the metallic plates is studied. An external magnetic field is applied along the vertical direction between the plates in order to magnetize the ferrite. Numerical simulations using an in-house 3D code are carried out to obtain the multipactor RF voltage threshold in this kind of structures. The presented results show that the multipactor RF voltage threshold at certain frequencies becomes considerably lower than for the corresponding classical metallic parallel-plate waveguide with the same vacuum gap. ; This work was supported by the European Space Agency (ESA) under Novel Investigation in Multipactor Effect in Ferrite and other Dielectrics used in high power RF Space Hardware Contract AO 1-7551/13/NL/GLC, and partially by the Spanish Government (under coordinated R&D projects TEC2013-47037-C5-R and TEC2014-55463-C3-3-P).

[EN] 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 in part by the European Space Agency (ESA) through the Research Project Novel Investigation in Multipactor Effect in Ferrite and Other Dielectrics Used in High Power RF Space Hardware under Contract AO 1-7551/13/NL/GLC, in part by the Ministerio de Economia y Competitividad (Spanish Government) through Research and Development under Project TEC2016-75934-C4-1-R and Project TEC2016-75934-C4-2-R, and in part by the European Regional Development Fund under Project TEC2014-55463-C3-3-P. ; Vague Cardona, JJ.; Melgarejo-Lermas, JC.; Boria Esbert, VE.; Guglielmi, M.; Moreno Cambroreno, MDR.; Reglero Mangada, MS.; Mata-Sanz, R. (2019). Experimental Validation of Multipactor Effect for Ferrite Materials Used in L- and S-Band Nonreciprocal Microwave Components. IEEE Transactions on Microwave Theory and Techniques. 67(6):2151-2161. https://doi.org/10.1109/TMTT.2019.2915546 ; S ; 2151 ; 2161 ; 67 ; 6

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.