An EM Tuning Procedure for Planar Filters Based on Individual Resonator Decomposition

Planar filters directly implemented by design formulas yield a distorted frequency response, especially at higher frequencies, due to dispersion and discontinuities. In this letter, an electromagnetic (EM) tuning procedure based on individual resonator decomposition for a fifth order stepped impedance resonator (SIR) filter is presented. The EM simulation of the SIR filter composed by the tuned resonators shows remarkable agreement with the design formula and requires no further tuning. The procedure is experimentally verified by comparing the measured and the simulation results.