Design of Broadband Interdigital BPF Using Low-Temperature Co-Fired Ceramic(LTCC) Technology for The Improvement of Bandstop Range

This paper proposes a 7th order interdigital band-pass filter using LTCC technology to achieve miniaturization and S-band pass characteristics. To eliminate harmonics, the proposed structure includes vias placed at 1mm intervals around the edges, which not only suppress harmonic components but also improve frequency selectivity. The proposed filter implements a broadband filter with a center frequency of 3GHz and a bandwidth of 2GHz. The implemented filter has an insertion loss of -0.79dB and a return loss of -29.42dB in the specified frequency band, and it is miniaturized to a size of 13.5 × 7 × 1.45 [mm3]. © The Korean Institute of Electrical Engineers.