264 MHz HTS Lumped Element Bandpass Filter

摘要

A 5-pole lumped element bandpass filter (BPF) of center frequency264.05 MHz and fractional bandwidth (FBW) 0.76/100 is designed andfabricated using Yba_2Cu_3O_(7-d) (YBCO) thin films de- posited onboth sides of a MgO substrate(40 mm × 40 mm × 0.5 mm). The returnloss, minimum insertion loss and ripple were measured to be 20.0 dB,less than 0.1 dB and less than 0.1 dB at 70 K, respectively. Theseresults verify both the compactness and low loss characteristics inthe VHF band. The simulated frequency response, where the fre- quencydependences of inductance (L) and capacitance (C) elements andhousing effect are taken into account, is in good agreement with themeasured frequency response.