Microstrip Hairpin Bandpass Filter for Radar S-Band with Dumbbell-DGS

摘要

One of the possible errors in radar communication is the presence of unwanted frequencies that are still passed by the radar system, causing performance to decrease. This paper proposes a bandpass filter (BPF) design for S-Band radars that work in the range of 3 GHz. A Bandpass filter is designed using the microstrip hairpin technique plus the dumbbell-Defected Ground Structure (DGS) method. This study aims to prove that the selection of DGS forms and effectiveness in optimization can provide better results. The band-pass filter is realized using the RO4350-B material with a relative dielectric constant of 3.48 and a thickness of 1.524 mm. The results obtained from the realization of band-pass filters show S₁₁ of -31.822 dB, S₂₁ of -0.829 dB and VSWR of 1.502. Filters work on ranges 2.850 - 3.02 GHz with a bandwidth of 170 MHz. From the parameters of the results obtained, the filter designed is following the specifications specified. Addition of dumbbell-DGS also gives better results than the form of a square groove-DGS.