@conference {09_URSIESP_MedinaRuiz-CruzMesaEtAl_EOTSinPlasmones, title = {Transmisi{\'o}n Extraordinaria sin Plasmones de Superficie}, booktitle = {Proc. 2009 Simposium Nacional URSI (in Spanish)}, year = {2009}, month = {Sept.}, pages = {1-4}, abstract = {This letter reports on the experimental demonstration of the extraordinary transmission (ET) phenomenon in a closed waveguide system having a diaphragm with an electrically small hole in it. The theoretical explanation for this phenomenon, which has formerly been studied only in periodically perforated screens, is here based on the concept of impedance matching. The concept of impedance matching is an alternative explanation to the surface plasmon polariton (SPP) theory and also accounts for ET through periodically perforated screens. The main difference between the two approaches lies on the fact that SPP{\textquoteright}s are not present in the proposed non-periodic system (an arbitrary cross section closed waveguide), and therefore it is not clear how the SPP-based theory could be applied. On the contrary, the simple equivalent circuit model resulting from the impedance matching point of view leads to numerical predictions that agree very satisfactorily with the experimental results.}, url = {http://w3.iec.csic.es/ursi/articulos_modernos/Cantabria2009/files/EOTSinSPP_FMedina_URSI09_v11241453622.pdf}, author = {Medina-Mena, F and J A Ruiz-Cruz and Mesa-Ledesma, F L and Montejo-Garai, J R and Rebollar, J M and Marques-Sillero, R} } @conference {07_IMS_Ruiz-CruzZhangRebollarEtAl_TEMMode-MatchingAnalysis, title = {TEM Mode-Matching Analysis of Multi-coupled Strip-line Filters}, booktitle = {2007 IEEE MTT-S International Microwave Symposium Digest}, year = {2007}, month = {June}, pages = {541-544}, abstract = {The analysis of multi-coupled strip-line filters by the mode-matching method is studied for different input/output excitations. The aim is to compare the computational effort of two different options and to propose the most suitable formulation for the design of some strip-line filters. It is shown that a suitable segmentation of the structure is essential for obtaining good numerical results. In fact, if the optimum segmentation is selected, a mode-matching analysis using only TEM modes can resemble the full-wave response, with shorter computation time. Hence, this approach can be very useful in design and different examples are shown to validate it, using other numerical methods and measurements of a ten order filter.}, keywords = {microwave filters, mode matching, multicoupled strip-line filter design, optimum structure segmentation, strip line filtersTEM mode-matching analysis}, issn = {0149-645X}, doi = {10.1109/MWSYM.2007.380546}, url = {http://ieeexplore.ieee.org/iel5/4263706/4263707/04263871.pdf?tp=\&isnumber=\&arnumber=4263871}, author = {J A Ruiz-Cruz and Zhang, Y and Rebollar, J M and Zaki, K A and Montejo-Garai, J R and Piloto, A J} }