A Novel Design of a Tri-Band Impedance Matching Network Based on the Concept of an Impedance Bridge

This paper proposes a novel concept of an Impedance Bridge for facilitating tri-band impedance matching. The same is implemented utilizing two meandered coupled lines in their all-pass configuration, linked by a
$\lambda/4$
transformer at a common reference frequency. The design calls for its simplicity, availability of design equations and optimization procedure and provision for enhancement of frequency as well as impedance transformation ratios. The proposed concept is validated with an RO4350 based fabricated prototype at three arbitrary and non-correlated frequencies of interest. The measured results are in good agreement with the simulations.