volume | PIER Journals

Abstract

A systematic procedure is presented for synthesis of generalized Chebyshev lossy bandstop filters with nonparaconjugate transmission zeros. From a lossy scattering parameters with the prescribed reflection zeros, the transformation formulas from the scattering matrix to the admittance matrix are obtained by reconstructing the non paraconjugate transmission zeros as paraconjugate ones. The canonical transversal array is modeled by partial fraction expansion of the normalized admittance functions, resulting in an increased order of the final network provided there are nonparaconjugate transmission zeros. The methods are simpler and more general than the ones in the literature. So it shows great versatility, and can also accommodate lossless network or a transfer function with symmetrical transmission zeros. To illustrate the proposed synthesis procedure, three typical examples have been carried out to validate the synthesis method.

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Dr. Guo Hui Li