Affiliated with the
Communication & Space
Sciences Laboratory

Nature Inspired Antenna Design

Equivalent Circuit Model Parameter Extraction

Passive microwave circuits require several thousand unknowns and large solve times when using direct full-wave electromagnetic modeling techniques


..: References :..

1-) Extraction of SPICE-Type Equivalent Circuits of Microwave Components and Discontinuities Using The Genetic Algorithm Optimization Technique
by Pingjuan L. Werner, Raj Mittra, and Douglas H. Werner

ABSTRACT: In this paper, the genetic algorithm (GA) is employed as an efficient optimization tool to derive SPICE-type equivalent circuits of microwave components, and of discontinuities in coaxial lines, from their specified S-parameters. Nodal analysis and techniques are utilized in conjunction with the GA to extract these equivalent circuits, whose component values are the parameters optimized by the GA. Numerical examples, that demonstrate the fact that GA yields excellent results for the cases studied, are included in the paper.




2-) Extraction of Equivalent Circuits for Microstrip Components and Discontinuities Using the Genetic Algorithm
by P. L. Werner, R. Mittra and D. H. Werner

ABSTRACT: This letter introduces a new technique based on the application of the genetic algorithm (GA) for extracting the equivalent circuits—from measured or computed S-parameters—that can be inserted into SPICE simulations. The GA is a robust optimization tool that is shown to yield excellent results for discontinuities in microstrip lines, for instance a right-angled bend, and for microwave circuits, e.g., planar inductors and parallel plate capacitors.




3-) A New Technique for the Extraction of SPICE-type Equivalent Circuits from Measured or Computed S-parameters of Microstrip Components and Discontinuities
by P. L. Werner and Raj Mittra
1997 IEEE International Symposium on Antennas and Propagation, Montreal, Canada, July 13-18.

ABSTRACT: This paper introduces a new technique based on the application of the Genetic Algorithm (GA) for extracting the equivalent circuits for measured or computed S-parameters that can be inserted into SPICE simulations. The GA is a robust optimization tool that is shown to yield excellent result for the sample test case of a right angle bend in a microstrop line.




4-) Genetic-Algorithm Optimization of Dipole Equivalent-Circuit Models
by B. R. Long, P. L. Werner and D. H. Werner

ABSTRACT: In this paper, we use a genetic-algorithm GA technique to optimize equivalent-circuit models of an antenna system. Two broadband equivalent-circuit models with component values are optimized by use of the genetic algorithm. The first is a conventional RLC network, while the second introduces a new technique that makes use of transmission-line segments as well as lumped components. Both equivalent circuits exhibit good impedance fidelity over a bandwidth exceeding five octaves, including the fundamental through the fourth overtone response.
Go/



5-) A Simple Broadband Dipole Equivalent Circuit Model
by B.R. Long, P.L. Werner and Doug Werner
2000 IEEE International Symposium on Antennas and Propagation, Salt Lake City, Utah, July 16-21

ABSTRACT: This paper presents a novel dipole equivalent circuit model exhibiting good impedance fidelity over a bandwith exceeding five octaves. A pair of transmission line segments duplicates the frequency-impedance periodicity of a dipole making broadband impedance fidelity possible with a minimum number of model components. Optimum model component values are found with the use of a genetic algorithm.




__ If you cannot open .PDF files please download Adobe Reader