An Efficient Filter Design via Optimized Rational-Function Fitting, without Similarity Transformation

  • Kahng Sung-Tek (Department of Information and Telecommunication Engineering, University of Incheon)
  • Published : 2006.09.01

Abstract

An efficient method is presented to design filters without the similarity transform of their coupling coefficient matrix as circuit parameters, which is very tedious due to pivoting and deciding rotation angles needed during the iterations. The transfer function of a filter is directly used for the design and its desired form is derived by the optimized rational-function fitting technique. A 3rd order coaxial lowpass filter is taken as an example to validate the proposed method.

Keywords

Passive Components;Microwave Filter;Coupling Coefficient Matrix;Rational Function;Optimization

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