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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

[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