A dual resonance high frequency bandpass filter

This paper presents a design of a dual resonance high-frequency bandpass filter using the Sonnet EM Simulator. The filter prototype is enhanced by adding the short stub in the center of the design. A parametric study shows the impact of choosing appropriate configuration characteristics. This is a dual resonance bandpass filter design, with center frequencies 7.8 GHz and 9.3 GHz. Performed input match S_11 at first resonance is-28.87 dB and insertion loss S_21 is -0.05 dB. The obtained results at second resonance are S_11=-8.97 dB and S_21=-2.74 dB. Due to its characteristics, this is a high-Q medium bandwidth dual resonance bandpass filter. The design is simulated and planning to be fabricated with 0.36 mm thickness and dielectric constant ?_r=1. This paper benefits from its compact size and simple geometry over the similar filters found in the literature.