Parallel-Planar High-Temperature Superconducting Dual-Band Bandpass Filter Using Double-Sided Conductors on a Substrate

This paper proposes a broadside coupling high-temperature superconducting (HTS) dual-band bandpass filter (DBPF) employing double-sided conductors on a substrate to suppress misalignment between resonators. This filter configuration satisfies the required specifications and provides flexibility in selecting each center frequency for the two passbands within certain ranges of frequencies. This paper presents 1.8-/2.9-GHz band and 2.1-/2.7-GHz band HTS bandpass filters, as experimental examples, to validate the proposed filter configuration. The measured frequency responses of the fabricated HTS-DBPFs are closer to the simulated ones than those of the previously proposed HTS-DBPF.