DUAL BAND FILTER DESIGN USING REAL FREQUENCY TECHNIQUE AND FREQUENCY TRANSFORMATION

Abstract

In this work, we present a frequency transformation based dual-band filter design approach using scattering
based real frequency technique. In the design process, conventional low-pass to band-pass frequency transformation is
integrated with the simplified real frequency technique to construct double pass-band filters. The approach is
particularly advantageous for designing matching filters between different termination resistances. As an alternative to
a direct low-pass to dual-band frequency transformation, the use of dual-band mapping on a normalized band-pass
prototype is investigated for efficient control of the passbands. Application of the proposed approaches for dual-band
filters is presented by comparative design examples.

Keywords

• Dual-band filters,frequency transformation,real frequency technique,band-pass prototype

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