@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} } @conference {06_IMS_ZhangRuiz-CruzZaki_RidgeWaveguideDivider, title = {Ridge Waveguide Divider Junctions for Wide-Band Multiplexer Applications}, booktitle = {2006 IEEE MTT-S International Microwave Symposium Digest}, year = {2006}, month = {June}, pages = {1225-1228}, abstract = {Ridge waveguide divider junctions are introduced and applied to wide-band multiplexer applications. A rigorous analysis and optimization process by mode matching method (MMM) is employed to design the junctions that yield low reflection coefficient in common port and almost equal transmission coefficients in the other two ports over a wide frequency band. Two design examples of wide-band diplexer and triplexer using such junctions are presented. All the components involved in the diplexer/triplexer designs are rigorously modeled and cascaded by MMM. Optimization procedures by MMM are also applied in these two designs to improve the performance. Multiplexers using such junctions can be built in either metallic form or low-temperature co-fired ceramic (LTCC) technology}, keywords = {low-temperature co-fired ceramics, mode matching, mode matching method, multiplexing equipment, ridge waveguide divider junctions, ridge waveguides, waveguide junctionsLTCC technology, wide-band diplexer, wide-band multiplexer applications, wide-band triplexer}, issn = {0149-645X}, doi = {10.1109/MWSYM.2006.249431}, url = {http://ieeexplore.ieee.org/iel5/4014788/4014789/04015143.pdf?tp=\&isnumber=\&arnumber=4015143}, author = {Zhang, Y and J A Ruiz-Cruz and Zaki, K A} } @conference {06_EuMC_Ruiz-CruzZhangFahmiEtAl_RidgeWaveguideElliptic, title = {Ridge Waveguide Elliptic Filters in Narrow-Wall Canonical Configuration}, booktitle = {Proc. 36th European Microwave Conference}, year = {2006}, month = {Sept.}, pages = {1080-1082}, abstract = {A new canonical ridge waveguide structure is proposed to design elliptic filter responses. The non-adjacent cavities are coupled by windows situated at the common narrow-wall of the ridge waveguide enclosures. This new configuration provides positive and negative cross couplings using evanescent rectangular waveguides and metallic strips, respectively. The full-wave analysis of the structure is carried out by a rigorous mode matching method. The design is based on circuit synthesis and full-wave optimization. Finally, the proposed structure is elucidated with the design of a four-pole filter and it is validated with the commercial HFSS software}, keywords = {circuit synthesis, elliptic filters, four-pole filter, full-wave optimization, metallic strips, mode matching, mode matching method, narrow-wall canonical configuration, negative cross couplings, network synthesis, nonadjacent cavities, positive cross couplings, rectangular waveguides, ridge waveguide elliptic filters, ridge waveguides, waveguide filtersHFSS software}, issn = {2-9600551-6-0}, doi = {10.1109/EUMC.2006.281121}, url = {http://ieeexplore.ieee.org/iel5/4057701/4057702/04058011.pdf?tp=\&isnumber=\&arnumber=4058011}, author = {J A Ruiz-Cruz and Zhang, Y and Fahmi, M M and Zaki, K A} } @article {05_IEEETMTT_Ruiz-CruzSabbaghZakiEtAl_Canonicalridgewaveguide, title = {Canonical ridge waveguide filters in LTCC or metallic resonators}, journal = {IEEE Transactions on Microwave Theory and Techniques}, volume = {53}, number = {1}, year = {2005}, month = {Jan.}, pages = {174-182}, abstract = {A new physical realization of an elliptic function filter response is proposed for achieving compact size, wide bandwidth, wide spurious free stopband and high-selectivity performance. The filter configuration can be implemented in conventional waveguide technology or embedded in a multilayer low-temperature co-fired ceramic structure for integration with other circuitry in a chip module. The filter is analyzed using rigorous mode matching. To validate the concept, prototypes of four- and six-cavity elliptic filters are designed following a systematic procedure. Approximate synthesis is used to obtain initial dimensions of the filter and the desired optimum response is obtained by means of a final full-wave optimization. The results are verified with other numerical methods and with the measurements of a fourth-order waveguide filter.}, keywords = {band-pass filters, canonical ridge waveguide filters, cavity resonator filters, ceramics, chip module, circuit optimisation, elliptic filters, elliptic function filter response, four cavity elliptic filters design, fourth order waveguide filter, full-wave optimization, metallic resonators, microwave filters, mode matching, multilayer low temperature cofired ceramic structure, multilayers, numerical methods, prototypes, resonators, ridge waveguides, six cavity elliptic filters design, spurious free stopband filter, waveguide filters band pass filters, waveguide technology}, issn = {0018-9480}, doi = {10.1109/TMTT.2004.839324}, url = {http://ieeexplore.ieee.org/iel5/22/30125/01381687.pdf?tp=\&arnumber=1381687\&isnumber=30125}, author = {J A Ruiz-Cruz and El Sabbagh, M A and Zaki, K A and Rebollar, J M and Zhang, Y} } @conference {05_IMS_Ruiz-CruzZhangZakiEtAl_Ridgewaveguidebranch-line, title = {Ridge waveguide branch-line directional couplers for wideband applications and LTCC technology}, booktitle = {2005 IEEE MTT-S International Microwave Symposium Digest}, year = {2005}, month = {June}, pages = {1219-1222}, abstract = {A new branch-line directional coupler is proposed for achieving wide bandwidth. The device is implemented in ridge waveguide to exploit its wide monomode band. It can be physically realized either in empty ridge waveguide or in LTCC for integration in a chip module. Two prototypes of two and five branches are designed following a systematic procedure. An appropriate equivalent circuit provides initial dimensions and the desired optimum response is obtained by means of a final full-wave optimization based on the rigorous and efficient mode-matching method. The results are verified with the finite element method of the HFSS software and a prototype will be manufactured for testing}, keywords = {branch-line directional couplers, chip module integration, directional couplers, equivalent circuits, finite element analysis, finite element method, full-wave optimization, mode matching, mode-matching method, optimisation, ridge waveguides, ridge waveguidesLTCC technology, wide monomode band}, issn = {01490-645X}, doi = {10.1109/MWSYM.2005.1516896}, url = {http://ieeexplore.ieee.org/iel5/10171/32491/01516896.pdf?tp=\&isnumber=\&arnumber=1516896}, author = {J A Ruiz-Cruz and Zhang, Y and Zaki, K A and Piloto, A J and Rebollar, J M} }