A superconducting dual‐band bandpass filter with a mixture of bandpass and bandstop sub‐filters is presented. The bandpass sub‐filter is designed with λ/2 double spiral resonators mid‐tapped by λ/4 connecting lines which act as admittance inverters. The tap position of each resonator is adjusted to meet the required susceptance slope parameter. The bandstop sub‐filter is designed with λ/2 folded resonators embedded in and coupled with the centres of the λ/4 connecting lines. The dual‐band filter is designed and fabricated on an LaAlO3 substrate with a compact size of 30.4 × 10.3 mm. The measurements show good dual‐band response and match well with the simulations.
A compact superconducting lowpass filter (LPF) composed of a pair of symmetrical parallel coupled lines, a cross-shaped patch and a modified E-type feeding structure is proposed. The filter is successfully designed and fabricated on MgO substrate with a compact size of 10.0 × 15.0 mm. Measured results match well with simulation results. The LPF has a 3 dB cutoff frequency of 2.18 GHz, relative stopband bandwidth of 160%, and 0.06 dB insertion loss in the passband. For attenuation level of −18.5 dB, stopband bandwidth is from 3.16 to 19.25 GHz.
A tri-band superconducting filter at L-band comprising three high-pole single-band sub-filters with sharp band-edges is presented to meet the high selectivity requirement. Matching junctions with high-impedance branch lines are used to connect the sub-filters and to reduce the channel interactions. MgO and LaAlO 3 substrates are utilised in the design and fabrication procedure to reduce the filter size and achieve a high performance. The whole filter has a compact size of 43 × 39.1 mm, and the measured results match well with the simulations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.