Synthesis and Design of a Wideband Filtering Impedance Transformer and its Application as a Power Divider
DOI:
https://doi.org/10.13052/2026.ACES.J.410409Keywords:
Filtering transformer, impedance transformer, isolation bandwidth, synthesis method, wideband power dividerAbstract
In this paper, two classes of impedance transformers with wide operating bandwidth are presented. The impedance parameters can be directly determined based on the specified impedance transformation ratio, fractional bandwidth (FBW), and in-band return loss (RL) requirements. To validate the proposed method, an impedance transformer is designed at the center frequency (f0) of 2.4 GHz and an impedance-transforming ratio (r) of 0.5. The filtering impedance transformer with FBW = 90% and RL=20dB is fabricated and measured, validating the theoretical prediction. Furthermore, to demonstrate its application potential, the second impedance transformer is employed to realize a filtering power divider with wide operating bandwidth and enhanced isolation bandwidth.
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