The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform

K A Zaki - One of the best experts on this subject based on the ideXlab platform.

  • characteristics of generalized Rectangular and circular ridge Waveguides
    IEEE Transactions on Microwave Theory and Techniques, 2000
    Co-Authors: Yu Rong, K A Zaki
    Abstract:

    Generalized ridge Waveguides are analyzed using the mode-matching method. The characteristic impedance, attenuation, and power-handling capability of several types of ridge Rectangular Waveguides and ridge circular Waveguides are presented. Numerical results are obtained, which are useful in the design of many microwave components and subsystems.

  • full wave modeling of conducting posts in Rectangular Waveguides and its applications to slot coupled combline filters
    IEEE Transactions on Microwave Theory and Techniques, 1995
    Co-Authors: Huiwen Yao, K A Zaki, A E Atia, R Hershtig
    Abstract:

    A full wave model of conducting posts in Rectangular Waveguides yielding their generalized S-matrix is presented. By cascading the generalized scattering matrices of the posts and waveguide discontinuities, slot couplings between two combline resonators are obtained. The validation and accuracy of the method are confirmed by comparing the numerical results with measured data. It is shown that both electric and magnetic couplings can be obtained by changing the slot positions, and the electric coupling is more sensitive to the tuning screw than magnetic coupling. A 6-pole slot coupled combline filter with asymmetrical transmission zeros is designed and built. Excellent filter responses are obtained.

  • modeling of cylindrical dielectric resonators in Rectangular Waveguides and cavities
    International Microwave Symposium, 1993
    Co-Authors: Xiaopeng Liang, Hsin-chin Chang, K A Zaki
    Abstract:

    Two methods for the accurate modeling of cylindrical dielectric resonators in Rectangular Waveguides and cavities are presented. The dielectric resonators can be general. The first method uses the mode matching technique with two derived series for analytical integrations of the inner products at the boundary between cylindrical and waveguide regions. The only requirement for this method concerning the dielectric resonator is that all its boundaries by cylindrical. The second method slices the configuration to small sections and treats each section as a uniform waveguide. It approximates the cylindrical regions by slices of Rectangular dielectric loaded Waveguides, and computes the generalized scattering matrix of the total structure by cascading the generalized scattering matrices of the individual slices and junctions. Using these accurate models, planar dielectric resonators can be analyzed. >

  • Modeling of dielectric objects in Rectangular Waveguides and cavities
    1994 IEEE MTT-S International Microwave Symposium Digest (Cat. No.94CH3389-4), 1
    Co-Authors: Hsin-chin Chang, K A Zaki
    Abstract:

    This paper proposed an approach to analyze dielectric objects in Rectangular Waveguides and cavities using generalized scattering matrices. The configurations are approximated by cascadings of dielectric loaded Waveguides. Flexibility and expandability are the major advantages of this approach. It is found that the proposed method is accurate in dealing with various kinds of Rectangular dielectric loaded waveguide transitions and dielectric objects in Rectangular Waveguides and cavities. >

J.r. Mosig - One of the best experts on this subject based on the ideXlab platform.

  • a novel efficient technique for the calculation of the green s functions in Rectangular Waveguides based on accelerated series decomposition
    IEEE Transactions on Antennas and Propagation, 2008
    Co-Authors: Francisco Javier Perez Soler, Fernando Daniel Quesada Pereira, David Canete Rebenaque, Alejandro Alvarez Melcon, J.r. Mosig
    Abstract:

    A new efficient technique for computing the Green's functions inside Rectangular Waveguides is presented. After a summary of the classical approaches and their difficulties, a new strategy is proposed, based on the decomposition of the main spectral series into simpler terms. Although the resulting series present better convergence rate, several acceleration techniques are combined to further improve the efficiency. Several results are presented to demonstrate the improvements in convergence rates obtained using the new decomposition.

  • An Integral-equation technique for solving thick irises in Rectangular Waveguides
    IEEE Transactions on Microwave Theory and Techniques, 2006
    Co-Authors: I. Stevanovic, P. Crespo-valero, J.r. Mosig
    Abstract:

    This paper presents an efficient integral-equation (IE) technique for analysis of thick irises inside multilayered Rectangular Waveguides. The IEs remain the same as in the case of zero-thickness iris and the thickness is accounted for only as a correction term in the IE kernel. This technique halves the number of unknowns on the iris, thus leading to computational effort and simulation times comparable to the zero-thickness case. In this paper, two efficient ways for computing the correction term are introduced and the accuracy of the approach is discussed on several waveguide structures and filters

F Arndt - One of the best experts on this subject based on the ideXlab platform.

  • rigorous analysis of arbitrarily shaped h and e plane discontinuities in Rectangular Waveguides by a full wave boundary contour mode matching method
    IEEE Transactions on Microwave Theory and Techniques, 1995
    Co-Authors: J M Reiter, F Arndt
    Abstract:

    A rigorous boundary contour mode-matching (BCMM) method is presented for the efficient calculation of the modal scattering matrix of arbitrarily shaped Hand E-plane discontinuities, junctions, and/or obstacles in Rectangular Waveguides. For the inhomogeneous waveguide region with general contour, the field is expanded in the complete set of cylindrical wave functions. The full-wave expansion allows the immediate rigorous inclusion of cascaded structures such as combined H- and E-plane bends. The efficiency of the method is demonstrated at the rigorous design of useful waveguide components which could not be modeled by mode-matching technique so far: cylindrical post-compensated H-plane T-junction, mitered H-plane and E-plane bends of arbitrary angle, cascaded H-/E-plane bends, circular post-coupled filter, E-plane filter with rounded corners, 180/spl deg/ rat race structure, and side-coupled dual TE/sub 311//TE/sub 113/-mode filter. The theory is verified by measurements. >

  • rigorous modal s matrix analysis of the cross iris in Rectangular Waveguides
    IEEE Microwave and Guided Wave Letters, 1992
    Co-Authors: R Ihmels, F Arndt
    Abstract:

    A rigorous field theory analysis is presented for cross-irises in Rectangular Waveguides, as well as for cross-iris coupled Rectangular waveguide resonators. Arbitrary iris location, unequal E-and H-plane cross size and finite thickness are rigorously taken into account. The scattering parameters of a cross-iris coupled one-resonator filter in the waveguide Ku-band (12-18 GHz) are presented as a calculation example. The theory is verified by comparison with available data for cut-off frequencies, as well as with measurements. >

  • a boundary contour mode matching method for the rigorous analysis of cascaded arbitrarily shaped h plane discontinuities in Rectangular Waveguides
    IEEE Microwave and Guided Wave Letters, 1992
    Co-Authors: J M Reiter, F Arndt
    Abstract:

    A rigorous boundary contour mode-matching (BCMM) method is presented for the efficient calculation of the modal scattering matrix of cascaded, arbitrarily shaped H-plane discontinuities, junctions and/or obstacles in Rectangular Waveguides. For the inhomogeneous waveguide region with general contour, the field is expanded in the complete set of cylindrical wave functions. The mode-matching technique is applied at the boundary to the waveguide ports and is shown to yield quick convergence and high numerical stability. Moreover, the modal scattering matrix of the corresponding region is obtained directly. The generalized modal scattering matrix technique achieves the rigorous and flexible modeling of composed H-plane waveguide structures of arbitrary cross-section, including the higher-order mode interactions at all discontinuities, such as of inductive iris coupled filters with resonators of more general shape. The theory is verified by comparison with results obtained by other methods. >

Huiwen Yao - One of the best experts on this subject based on the ideXlab platform.

  • full wave modeling of conducting posts in Rectangular Waveguides and its applications to slot coupled combline filters
    IEEE Transactions on Microwave Theory and Techniques, 1995
    Co-Authors: Huiwen Yao, K A Zaki, A E Atia, R Hershtig
    Abstract:

    A full wave model of conducting posts in Rectangular Waveguides yielding their generalized S-matrix is presented. By cascading the generalized scattering matrices of the posts and waveguide discontinuities, slot couplings between two combline resonators are obtained. The validation and accuracy of the method are confirmed by comparing the numerical results with measured data. It is shown that both electric and magnetic couplings can be obtained by changing the slot positions, and the electric coupling is more sensitive to the tuning screw than magnetic coupling. A 6-pole slot coupled combline filter with asymmetrical transmission zeros is designed and built. Excellent filter responses are obtained.

  • Modeling of generalized coaxial probes in Rectangular Waveguides
    IEEE Transactions on Microwave Theory and Techniques, 1995
    Co-Authors: Huiwen Yao, Kawthar A. Zaki
    Abstract:

    A rigorous approach combining the orthogonal expansion method for modeling cylindrical posts in Rectangular Waveguides and the extension of the three short plane technique is introduced to obtain the S-matrix for a general coaxial probe in a Rectangular waveguide. A cascading procedure is applied to solve the problem of a probe near a waveguide discontinuity and to obtain the response of a probe-excited band pass filter. The computed results are in excellent agreement with the measured results showing the usefulness of this method.

R Hershtig - One of the best experts on this subject based on the ideXlab platform.

  • full wave modeling of conducting posts in Rectangular Waveguides and its applications to slot coupled combline filters
    IEEE Transactions on Microwave Theory and Techniques, 1995
    Co-Authors: Huiwen Yao, K A Zaki, A E Atia, R Hershtig
    Abstract:

    A full wave model of conducting posts in Rectangular Waveguides yielding their generalized S-matrix is presented. By cascading the generalized scattering matrices of the posts and waveguide discontinuities, slot couplings between two combline resonators are obtained. The validation and accuracy of the method are confirmed by comparing the numerical results with measured data. It is shown that both electric and magnetic couplings can be obtained by changing the slot positions, and the electric coupling is more sensitive to the tuning screw than magnetic coupling. A 6-pole slot coupled combline filter with asymmetrical transmission zeros is designed and built. Excellent filter responses are obtained.