Compact bandpass filter with wide stopband using stepped impedance resonators

Abstract

A compact bandpass filter with wide stopband using stepped impedance resonators has been designed and fabricated. And open ended stubs for frequency fine tuning are introduced. The new passband filter was analyzed, simulated and fabricated. Measured results are in good agreement with the electromagnetic simulation results. Moreover the circuit only occupies 20.1 × 17.1 mm2(≈0.21 λg × 0.16λg).