@article {11_IEEEMWCL_Montejo-GaraiRuiz-CruzRebollar_In-lineEPlaneBandStop,
	title = {In-line Pure E-Plane Waveguide Band-Stop Filter with Wide Spurious-Free Response},
	journal = {IEEE Microwave and Wireless Components Letters},
	volume = {21},
	number = {4},
	year = {2011},
	month = {April},
	pages = {209-211},
	abstract = {A new compact pure E-plane waveguide structure is proposed for coupling band-rejection cavities to the main rectangular waveguide in bandstop in-line filters. This coupling structure reduces drastically the unwanted resonances in filters with a very large pass band requirement. Moreover, it has some additional advantages. First, unlike typical inductive irises, large coupling coefficients can be implemented. Second, a pure E-plane configuration is achieved, which simplifies the manufacturing and also reduces significantly the computational effort. Third, in the design, by means of distributed model circuits, the rejection cavities are individually designed and connected by phase shifters maintaining the E-plane layout. Experimental validation is demonstrated by a pseudoelliptic fifth-order bandstop filter centered at 28 GHz and 2\% fractional stop band. It is free of spurious resonances in the full Ka-band.},
	issn = {1531-1309},
	doi = {10.1109/LMWC.2011.2105468},
	url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5723025\&tag=1},
	author = {Montejo-Garai, J R and J A Ruiz-Cruz and Rebollar, J M and Estrada, T.}
}
@conference {05_EIEC_Montejo-GaraiRuiz-CruzRebollar_Implementaciondefiltros,
	title = {Implementaci{\'o}n de filtros con ceros de transmisi{\'o}n mediante polos extra{\'\i}dos en tecnolog{\'\i}a plano-H},
	booktitle = {Proc. IV Encuentro Ib{\'e}rico de Electromagnetismo Computacional (in Spanish)},
	year = {2005},
	month = {Sept.},
	pages = {1-5},
	author = {Montejo-Garai, J R and J A Ruiz-Cruz and Rebollar, J M}
}
@conference {04_URSIUSA_Ruiz-CruzRebollar_Interpretationofresonance,
	title = {Interpretation of resonance at inclined multi-aperture rectangular iris with arbitrary locations in rectangular waveguide},
	booktitle = {Proc. 2004 USNC/URSI National Radio Science Meeting},
	year = {2004},
	month = {June},
	pages = {45},
	abstract = {Alternative interpretation of resonance of two-apertures iris in terms of the excitation of a TEM field of the structure was proposed by the authors of this contribution at (2003 USNC/URSI Symp., 226). This alternative interpretation proposed is very simple and useful to design bandpass filters with some improved stopband attenuation as it has been proposed at (L. Mospan, VIII Int. Conf. MMET, 503-505, 2000) and more recently at (A A Kirilenko, MSMW{\textquoteright}2001 Symposium, 690-692). Moreover, this interpretation could be useful to prevent some spurious resonances that arise at some rectangular waveguide devices, therefore helping the designer to improve their electrical performances. In this paper, with the main aim to confirm our alternative interpretation of the resonance in terms of a TEM field excitation, we consider a modification of the previous ones: a new iris structure composed by inclined multi-aperture rectangulars. The single inclined aperture was analytically analysed at (R Yang and A S Omar, IEEE Trans. MTT- 41, 1461-1463), and the inclined multi-aperture iris by means of the Generalised Scattering Matrix of generalised 2-port discontinuity concept (J M Rebollar, IEE Proc., 1-7, 1988). The analysis of the scattering parameters joint to a visualisation of the electromagnetic field vectors in the structure are employed to discuss and validate the interpretation of the resonance. As a first example, an iris with only two rectangular apertures is considered. The excitation of the only one TEM-resonance is analysed vs. the inclination between the apertures and the waveguide walls. A second example of an iris with three rectangular apertures is analysed too. The excitation of the two TEM-resonances of this iris it is also studied. Quantitative results for the resonance frequency positions and field plots at these frequency points for the above mentioned examples will be presented. The obtained results for the inclined two/three-apertures irises validate the interpretation of resonances in terms of the excited TEM fields.},
	author = {J A Ruiz-Cruz and Rebollar, J M}
}
@conference {03_EIEC_Ruiz-CruzRebollar_Interpretaciondelas,
	title = {Interpretaci{\'o}n de las resonancias de irises multiapertura y su aplicaci{\'o}n al dise{\~n}o de filtros},
	booktitle = {Proc. III Encuentro Ib{\'e}rico de Electromagnetismo Computacional (in Spanish)},
	year = {2003},
	month = {Dec.},
	pages = {1-4},
	abstract = {La utilizaci{\'o}n de irises multiapetura para el dise{\~n}o de filtros paso banda presenta inter{\'e}s tanto por su bajo coste y reducido volumen como por la posibilidad de obtener mejores prestaciones el{\'e}ctricas en particular consiguiendo una mayor atenuaci{\'o}n fuera de la banda de paso. Diferentes aproximaciones se han venido realizando para predecir las resonancias producidas por estos elementos, desde las m{\'a}s cl{\'a}sicas y secillas aproximaciones circuitales [1], hasta las m{\'a}s precisas y recientes caracterizaciones electromagn{\'e}ticas de onda completa [2]. Adem{\'a}s de la caracterizaci{\'o}n precisa de estas resonancias, resulta de inter{\'e}s poseer una interpretaci{\'o}n f{\'\i}sica de las mismas, tanto por poseer un conocimiento m{\'a}s profundo de las mismas, como por la ayuda que pueda presentar al dise{\~n}o de dispositivos. En esta direcci{\'o}n han aparecido dos trabajos [3] y [4] en los que se interpretan las resonancias en t{\'e}rminos de "oscilaciones naturales" en la estructura abierta as{\'\i} como una generalizaci{\'o}n de dichos irises multiapertura para el dise{\~n}o de filtros. En esta contribuci{\'o}n, se presenta una interpretaci{\'o}n alternativa de las resonancias de los irises multiapertura en t{\'e}rminos de la excitaci{\'o}n de campos de tipo TEM que pueden aparecer en la estructura. En el caso m{\'a}s sencillo de un iris con dos aperturas, el campo tipo TEM considerado viene soportado por dos conductores, que en este caso ser{\'\i}an el strip existente entre las dos aperturas del iris y las propias paredes de la guia. Esta "l{\'\i}nea de transmisi{\'o}n" se encontrar{\'\i}a cortocircuitada en sus extremos y por tanto su longitud total se corresponder{\'\i}a con el ancho de las aperturas. Nos encontramos por tanto con una l{\'\i}nea de transmisi{\'o}n cortocircuitada que deber{\'\i}a presentar una resonancia a la frecuencia en que su longitud sea lambda/2. Una caracterizaci{\'o}n precisa, un estudio de las excitaciones de dichos campos resonantes, as{\'\i} como una visualizaci{\'o}n de los mismos servir{\'a} para confirmar la validez de la interprestaci{\'o}n que se propone en esta contribuci{\'o}n. Se presentar{\'a} un amplio abanico de resultados para validar la interpretaci{\'o}n propuesta. Esta sencilla interpretaci{\'o}n de las resonancias puede resultar de gran utilidad tanto a la hora de utilizarlas para el dise{\~n}o de filtros, como para impedir la aparic{\'o}n de esp{\'u}rios en otros dispositivos en gu{\'\i}a.},
	author = {J A Ruiz-Cruz and Rebollar, J M}
}
