A 2.4 GHz SlW-based circular resonator for bandpass filter application

A design of 2.4 GHz bandpass filter is developed based on Substrate Integrated Waveguide (SIW) using printed circuit board technology. The circular cavity structure using TM010 mode is employed in the design of this bandpass filter. To prove the concept, the filter structure is fabricated using Rogers RT5880 with dielectric constant, εr = 2.2 and height of substrate 1.57 mm. The design was simulated using high frequency circuit simulator and was measured using vector network analyzer. The measured results are in good agreement with simulated result. Slight frequency shift and losses are still in acceptable range.