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In this article, a novel and efficient approach for modeling radio-frequency microelectromechanical system (RF MEMS) resonators by using artificial neural network (ANN) modeling is presented. In the proposed methodology, the relationship between physical-input parameters and corresponding electrical-output parameters is obtained by combined circuit/full-wave/ANN modeling. More specifically, in order to predict the electrical responses from a resonator, an analytical representation of the electrical equivalent-network model (EENM) is developed from the well-known electromechanical analogs. Then, the reduced-order, nonlinear, dynamic macromodels from 3D finite-element method (FEM) simulations are generated to provide training, validating, and testing datasets for the ANN model. The developed ANN model provides an accurate prediction of an electrical response for various sets of driving parameters and it is suitable for integration with an RF/microwave circuit simulator. Although the proposed approach is demonstrated on a clamped-clamped (C-C) beam resonator, it can be readily adapted for the analysis of other micromechanical resonators. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14: 302–316, 2004. [ABSTRACT FROM AUTHOR]

This paper expands upon reported methods for utilizing prior knowledge for reducing complexity of input–output relationships that an ANN must learn. Previously, two simple methods, difference method and prior knowledge input method, were demonstrated for new model developments. This paper utilizes knowledge-based modeling techniques for novel microwave modeling applications. ©1999 John Wiley & Sons, Inc. Int J RF and Microwave CAE 9: 254–260, 1999. [ABSTRACT FROM AUTHOR]

A methodology for synthesis (leading to physical dimensions) of multilayer asymmetric coupled microstrip lines using artificial neural network models is presented. Models are appropriate for design and optimization of multilayer configurations for circuits like filters, baluns, and directional couplers. Proposed methodology is demonstrated by designing a two-layer coupled line filter. ©1999 John Wiley & Sons, Inc. Int J RF and Microwave CAE 9: 175–186, 1999. [ABSTRACT FROM AUTHOR]

A CAD approach based on the multiport network model (MNM) has been developed for the design/analysis of rectangular microstrip patches gap-coupled to a microstrip feed line. Microstrip patches on this substrates with and without a dielectric cover layer are considered. Results of the analysis for sample two-port patches are compared with experimental and moment method results. The agreement validates the proposed model and the analysis procedure. Application of the MNM approach to CAD of linear series-fed arrays of gap coupled rectangular microstrip patches is also discussed. [ABSTRACT FROM AUTHOR]

This article points out the possibility of obtaining nonsymmetrical Z-matrices when the contour integral method is used for analysis of a general-shaped, two-dimensional planar component even when the component is passive and reciprocal. The nonsymmetry is caused by dependence of the normal derivative of the Green's function on the geometry. This nonsymmetry may be reduced by increasing the number of sections on the contour or by selecting a Green's function such that its normal derivative on the contour is zero. [ABSTRACT FROM AUTHOR]

A general procedure for design and analysis of a Rotman-type beam-forming lens using 2-dimensional field analysis is proposed. Evaluation of reflection coefficients, coupling between ports, main beam direction, 3-dB beam width and side lobe level are described. The results for a sample case are in agreement with the experimental results. The procedure developed is suitable for CAD implementation leading to optimization of Rotman lens layout configuration. [ABSTRACT FROM AUTHOR]

Focuses on the various aspects of microwave computer-aided designs. Applications of different simulators for analyzing microstrip bandpass filter; Provision of actual current distribution on the filter structure; Presentation of a simple curve-fitted expression for the radiation resistance of rectangular microstrip antennas.

Presents several papers that relates to different aspects of microwave computer-aided design. Evaluation of the calculation method for the capacitance of generalized circular structures; Design concepts for a novel microwave active bandpass filter structure; Analysis of microstrip lines on isotropic and anisotropic substrates.

Provides an overview of several articles about radio frequency and microwave computer-aided engineering.

Focuses on topics related coplanar microwave technology published in the September 1996 issue of the "International Journal of Microwave and Millimeter Wave Computer-Aided Engineering." Development of coplanar microwave integrated circuits as an alternative to microstrip-based circuits; Advantages of using coplanar circuits; Analysis of shielded elevated coupled coplanar waveguide using a modified finite element method.

Provides an overview of the articles contained in the 1993 issue of "International Journal of Microwave and Millimeter-Wave Computer-Aided Engineering." Consideration of the issue as the part 1 of a two special issue on "CAD of Printed Antennas and Arrays"; Discussion of FD-TD analysis of parasitic mutual coupling among neighboring via-holes and between a via-hole and a microstripline in multilayer, three-dimensional circuit configurations; Presentation of a three-dimensional, finite element analysis of N-port waveguide junctions using edge-elements.

Introduces a series of articles published in the April 1991 issue of the journal "International Microwave and Millimeter-Wave Computer-Aided Engineering." Discussion of static approximations and full-wave analysis techniques in analyzing microstrip line discontinuities; Evaluation of the nonlinear circuit analysis using the method of harmonic balance; Application of supercomputers to the solution of advanced microwave circuit computer aided design problems.

Introduces several articles about computer-aided design of waveguide components and antennas.

Provides an overview of the topics to be featured in the upcoming issue of the "International Journal of Microwave and Millimeter-Wave Computer-Aided Engineering. Stripline-fed cylindrical slot antennas; SPICE model for angled multipin connectors; CAD of waveguide components and antennas; Network synthesis methods in microwave design.