@conference {06_IMS_ZhangRuiz-CruzZaki_RidgeWaveguideCoupled, title = {Ridge Waveguide Coupled Stripline Resonator Filters and Multiplexers}, booktitle = {2006 IEEE MTT-S International Microwave Symposium Digest}, year = {2006}, month = {June}, pages = {681-684}, abstract = {Stripline resonator bandpass filters with evanescent-mode coupling sections by ridge waveguides are introduced in this paper. Such filters have very compact cross sections, which makes them suitable choices for some integrated systems having cross section constraints. Low Temperature Co-fired Ceramic (LTCC) technology can be employed to build such filters for PCB systems. It is also possible to manufacture them in air-filled metallic structures. Two filter design examples by Mode Matching Method (MMM) are given in this paper. Stepped impedance line resonators are used in one example to improve the spurious. The presented filters can also be applied for multiplexer applications using stripline junctions. One diplexer design example for LTCC application is presented to show the feasibility.}, issn = {0149-645X}, doi = {10.1109/MWSYM.2006.249724}, url = {http://ieeexplore.ieee.org/iel5/4014788/4014789/04014995.pdf?tp=\&isnumber=\&arnumber=4014995}, author = {Zhang, Y and J A Ruiz-Cruz and Zaki, K A} } @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} } @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} }