Miniaturized Microstrip Lowpass Filter using Asymmetric Stepped-Impedance Hairpin Resonator and Slotted Ground Plane

In this paper, a newly compact low pass filter is introduced. This filter is constructed by using novel asymmetric stepped-impedance hairpin resonator and slotted ground plan for size reduction and spurious suppression. Furthermore, the equivalent-circuit model of the proposed resonator is set up and analyzed. Additionally, slotted ground plane are adopted to obtain a good stop band characteristics. Finally, this compact filter was designed, fabricated, and measured. The experimental results of the filter have a good agreement with the simulated results.