@conference {13_EuMC_Leal-SevillanoRuiz-CruzMontejo-GaraiEtAl_CompactBroadbandCouplersMagicT,
	title = {Compact Broadband Couplers Based on the Waveguide Magic-T Junction},
	booktitle = {Proc. 43rd European Microwave Conference},
	year = {2013},
	issn = {978-1-61284-235-6},
	author = {C A Leal-Sevillano and J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@conference {11_EuMC_Leal-SevillanoRuiz-CruzMontejo-GaraiEtAl_CADDual-BandPolarizersCorrugatedRectWg,
	title = {CAD for Dual-Band Polarizers in Corrugated Rectangular Waveguide},
	booktitle = {Proc. 41st European Microwave Conference},
	year = {2011},
	month = {Oct.},
	pages = {822-825},
	abstract = {Waveguide polarizers are essential devices in feeders for radio transmission systems with circular polarization. In this paper two different dual-band polarizers are designed and compared. The structure of both polarizers is based on the classical corrugated rectangular waveguide. This structure can be analyzed very efficiently like an H-plane and an E-plane problem. The Mode-Matching technique, in combination with global search algorithms, is used for the full-wave analysis and optimization of the polarizers. In the first polarizer, the height of the corrugations is designed according to a taper-type shape. For the second polarizer, no restrictions in the height of the corrugations are imposed and all the dimensions are optimized. The performance of both polarizers is compared, showing certain improvement in terms of polarization purity for the second one.},
	keywords = {corrugated waveguide, dual-band, mode-matching, optimization, Waveguide polarizers},
	issn = {978-1-61284-235-6},
	url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=224789},
	author = {C A Leal-Sevillano and J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@book {10_INTECHBook_Ruiz-CruzMontejo-GaraiRebollar_CADWgDevicesbyMM,
	title = {Computer Aided Design of Waveguide Devices by Mode-Matching Methods (in Microwave and Millimeter Wave Technologies (ISBN: 978-953-307-083-4))},
	year = {2010},
	month = {Oct 2009},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M},
	editor = {Zhurbenko, V}
}
@article {09_ELET_Ruiz-CruzMontejo-GaraiRebollarEtAl_C-BandOMT,
	title = {C-Band Orthomode Transducer for Compact and Broadband Antenna Feeders},
	journal = {Electronics Letters},
	volume = {45},
	number = {16},
	year = {2009},
	month = {July},
	pages = {813-814},
	abstract = {The design and evaluation of a compact C-band orthomode transducer for dual polarisation satellite communications is presented, covering the bands 3.7-4.2 GHz and 5.925-6.425 GHz (54\% of fractional bandwidth separation). Over such a broadband, the main difficulty is to obtain a compact structure able to fulfil the stringent satellite specifications with minimum longitudinal length. The proposed configuration, validated with a tested prototype, also reduces the number of connections and parts in the fabrication, decreasing the passive intermodulation risk and the mass and volume},
	issn = {0013-5194},
	doi = {10.1049/el.2009.1034},
	url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5191333\&isnumber=5191328?tag=1},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M and Montero, J M}
}
@article {08_PIER_Ruiz-CruzMontejo-GaraiRebollar_CompactKuTriplexer,
	title = {Compact Full Ku-Band Triplexer With Improved E-Plane Power Divider},
	journal = {Progress in Electromagnetic Research},
	volume = {86},
	year = {2008},
	month = {October},
	pages = {39-51},
	abstract = {An improved E-plane power divider for compact waveguide triplexers with large separation between channels is presented. The configuration of the divider aims to exploit the different behavior of the device for frequency bands with large separation, leading to a very asymmetric E-plane junction. H-plane filters with inductive windows are used for each channel, in order to obtain reduced insertion losses and lower sensitivity than in metal-insert E-plane filters. The resultant triplexer configuration is very compact, and its design is analyzed and optimized by Mode-Matching. The experimental results of a full Ku-band prototype for communications satellite systems show a very good agreement with the expected simulated response.},
	issn = {1559-8985},
	doi = {10.2528/PIER08082803},
	url = {http://ceta.mit.edu/pier/pier86/03.08082803.pdf},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M and Sobrino, S.}
}
@conference {08_URSIUSA_Ruiz-CruzMontejo-GaraiRebollar_ComparisonofDifferent,
	title = {Comparison of Different Models to Obtain the Dispersion Diagrams of Transmission Lines at Terahertz Frequencies},
	booktitle = {Proc. 2008 USNC/URSI National Radio Science Meeting},
	year = {2008},
	month = {July},
	pages = {1},
	abstract = {Transmission lines for microwave through terahertz frequencies present an increasing interest for many research groups involved in the modelling of systems operating at these frequencies. In the theoretical characterization of waveguides at terahertz frequencies, the microwave engineering community must address two main challenges: a) the behaviour of metal conductors at this broad bandwidth requires a more evolved model than the constant conductivity model used at microwaves frequencies, and b) the Leontovich{\^A}{\textasciiacute}s conditions (surface impedance conductor model), widely used at lower frequencies to predict the conductor losses and the attenuation constant of the different waveguide modes, may not be accurate enough at frequencies in the terahertz range. In order to quantify the accuracy of the Leontovich{\^a}{\texteuro}{\texttrademark}s model, in this communication an analytic analysis for the parallel plate waveguide is proposed. It is based on a rigorous matching of the different field expressions at the interface between regions of the waveguide. For the conductor, it uses the model proposed in L Solymar classic book (Lectures on electrical properties of material, 1990, Oxford Science Pub). This model has shown its validity, for the authors, as far as a thousand of terahertzs, predicting very accurately the Surface Plasmon Polaritons on metallic surfaces (a dual structure of the parallel plate waveguide considered in this work, M Mansuripur et al., OPN April 2007, pp. 44-49). The propagation constant for fundamental (TM00 or quasi-TEM) and higher order modes (TM01 and TE01) are calculated by solving the corresponding characteristic equations (R E Collin, {\^a}{\texteuro}{\oe}Field theory of guided waves{\^a}{\texteuro} , 1991, IEEE Press), which provide the dispersion diagrams of the modes. The field pattern of the modes could be also obtained. A comparison between the dispersion diagrams obtained with the classical approach (Leontovich{\^a}{\texteuro}{\texttrademark}s approximation) and with the fullwave solution for different parallel plate dimensions will be presented. The errors for both phase and attenuation constants are quantified giving a precise idea on the validity of the different models from an engineering point of view. The results will be given for the fundamental and higher order modes.},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@conference {07_URSIESP_Ruiz-CruzMontejo-GaraiRebollarEtAl_CADdeOMTs,
	title = {CAD de OMTs (Ortho-Mode Transducers) de Banda Ancha Basados en la Uni{\'o}n B{\o}ifot},
	booktitle = {Proc. 2007 Simposium Nacional URSI (in Spanish)},
	year = {2007},
	month = {Sept.},
	pages = {1-4},
	abstract = {This paper proposes a CAD tool for wideband OMTs based on the B{\o}ifot junction which has two interesting features. First, the OMT routing branches use well-known waveguide elements, such as truncated E-plane bends, which can be efficiently analyzed by Mode-Matching (MM) methods and can achieve wideband performance. Second, a MM technique is presented for the four-port Boifot junction, which provides its generalized multimode characterization. As a result, the whole OMT is segmented into different regions, yielding an efficient CAD tool for its optimum design. The analysis method and the designed OMT have been validated with other numerical methods and experimental results.},
	url = {http://w3.iec.csic.es/ursi/articulos_desde_2007/la_laguna_2007/PDF/p208.pdf},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M and Montesano, C E and Mart{\i}n, M J and Naranjo-Masi, M}
}
@conference {06_CNES_Ruiz-CruzMontejo-GaraiRebollar_Comparisonofdifferent,
	title = {Comparison of different technologies to implement finite transmission zeros in cavity waveguide filters},
	booktitle = {Proc. 2006 Int. Workshop on Microwave Filters CNES-ESA},
	year = {2006},
	month = {Oct.},
	pages = {1-2},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@conference {06_IMS_Ruiz-CruzMontejo-GaraiRebollarEtAl_ComputerAidedDesign,
	title = {Computer Aided Design of Wideband Orthomode Transducers based on the Boifot Junction},
	booktitle = {2006 IEEE MTT-S International Microwave Symposium Digest},
	year = {2006},
	month = {June},
	pages = {1173-1176},
	abstract = {A CAD tool based on the Boslashifot junction is proposed for the design of wideband orthomode transducers (OMTs). It has two interesting features. First, the OMT routing branches use well-known waveguide elements, such as truncated E-plane bends, which can be efficiently analyzed by mode-matching (MM) methods and can achieve wideband performance. Second, a MM technique is presented for the four-port Boslashifot junction, which provides its generalized multimode characterization. As a result, the whole OMT is segmented into different regions, yielding an efficient CAD tool for its optimum design. The analysis method and the designed OMT have been validated with other numerical methods and experimental results},
	keywords = {CAD, computer aided design, four-port junction, mode matching, mode-matching methods, OMT routing branches, transducers, waveguide componentsCAD tool, waveguide elements, wideband orthomode transducers},
	issn = {0149-645X},
	doi = {10.1109/MWSYM.2006.249400},
	url = {http://ieeexplore.ieee.org/iel5/4014788/4014789/04015130.pdf?tp=\&isnumber=\&arnumber=4015130},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M and Montesano, C E and Mart{\i}n, M J and Naranjo-Masi, M}
}
@conference {02_APS_Ruiz-CruzMontejo-GaraiRebollar_Characterisationofwaveguide,
	title = {Characterisation of waveguide discontinuities with finite wall conductivity},
	booktitle = {Proc. 2002 IEEE Antennas and Propagation Society International Symposium},
	volume = {4},
	year = {2002},
	month = {June},
	pages = {428-431},
	abstract = {In this paper, a procedure is proposed to evaluate the generalised scattering matrix of waveguide discontinuities with finite wall conductivity. This approach is applied to evaluate the insertion losses in several waveguide structures of Chebyshev bandpass filters. These numerical results are compared with those obtained with other numerical methods and with measurements, validating the proposed procedure.},
	keywords = {band-pass filters, Chebyshev filters, electromagnetic wave scattering, finite wall conductivity, generalised scattering matrix, insertion losses, numerical methods, S-matrix theory, waveguide discontinuities, waveguide filters, waveguide theory Chebyshev bandpass filters},
	issn = {0-7803-7330-8},
	doi = {10.1109/APS.2002.1017013},
	url = {http://ieeexplore.ieee.org/iel5/7931/21884/01017013.pdf?tp=\&isnumber=\&arnumber=1017013},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@conference {01_ISS_Ruiz-CruzMontejo-GaraiRebollar_Somepropertiesof,
	title = {CAD of dual-mode filters with elliptical cavities},
	booktitle = {Proc. 11th International Travelling Summer School on Microwaves and Lightwaves},
	year = {2001},
	month = {July},
	pages = {11},
	author = {J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M}
}
@conference {01_EIEC_Montejo-GaraiRuiz-CruzRebollar_Comparacionentrediferentes,
	title = {Comparaci{\'o}n entre diferentes t{\'e}cnicas para el c{\'a}lculo de p{\'e}rdidas de inserci{\'o}n en filtros},
	booktitle = {Proc. II Encuentro Ib{\'e}rico de Electromagnetismo Computacional (in Spanish)},
	year = {2001},
	month = {Dec.},
	pages = {1},
	abstract = {El c{\'a}lculo de p{\'e}rdidas de inserci{\'o}n debido a la utilizaci{\'o}n de conductores reales para dispositivos pasivos de microondas en general y filtros en particular es una cuesti{\'o}n de gran importancia no s{\'o}lo te{\'o}rica, sino tambi{\'e}n pr{\'a}ctica. En particular para filtros de aplicaciones espaciales, esta especificaci{\'o}n puede llegar a ser una de las complicadas de satisfacer obligando en muchos casos a utilizar modos resonantes distintos del fundamental [1]. En este trabajo se presenta un estudio comparativo entre diferentes t{\'e}cnicas para determinar las p{\'e}rdidas y su comparaci{\'o}n con medidas experimentales. Las diferentes t{\'e}cnicas empleadas en este trabajo para su comparaci{\'o}n son: a) aproximaci{\'o}n circuital, en la que se considera simplemente la atenuaci{\'o}n del modo de resonancia del filtro [2], b) M{\'e}todo de Adaptaci{\'o}n Modal considerando las p{\'e}rdidas en los obst{\'a}culos- discontinuidades que constituyen la estructura real del filtro [3]. En esta t{\'e}cnica se considera que se satisfacen las condiciones de Leontovich en las paredes de la discontinuidad para realizar su posterior caracterizaci{\'o}n mediante GSM. c) M{\'e}todo Adaptaci{\'o}n Modal Multipuerta, propuesto en este trabajo y que considera el obst{\'a}culo-discontinuidad como nuevas gu{\'\i}as rellenas de material conductor. Se caracteriza el obst{\'a}culo mediante la Matriz de Dispersi{\'o}n Generalizada Multimodo Multipuerta y por {\'u}ltimo, d) M{\'e}todo de Elementos Finitos, haciendo uso de software comercial [4] Los resultados te{\'o}ricos de las t{\'e}cnicas enumeradas han sido comparados con medidas de diferentes filtros paso banda trabajando en las bandas X, K y Ka, y dise{\~n}ados para diferentes equipos embarcados en sat{\'e}lites. La comparaci{\'o}n realizada conduce a resultados calificables de entre curiosos y extra{\~n}os, y por el momento sin una explicaci{\'o}n que pueda considerarse satisfactoria. Todo ello, corrobora parcialmente los resultados de [3] para otras geometr{\'\i}as.},
	author = {Montejo-Garai, J R and J A Ruiz-Cruz and Rebollar, J M}
}
