In this paper, for the first time, we present a novel Pi-shaped structure using resonators for multiband applications. The multiband Pi-shaped structure with LC resonators is analyzed. In order to demonstrate the proposed multiband Pi-shaped structure, one tri-band Wilkinson power divider and one tri-band rat-race coupler are designed, fabricated, and tested. The compactness of the two demonstrated components is well kept by putting all stubs with resonators inside the components themselves. Measured results are in good agreement with the simulated results.
