We have designed and tested a superconducting coplanar waveguide (CPW) bandstop filter consisting of 8 coupled line sections at a center frequency of 1. 53 GHz. A packaged 94. 7% bandwidth low pass Chebychev design yielded a filter with a center frequency of 1. 56 GHz less than 1. 2 dB insertion loss in the passband and better than 28 dB rejection at 20 Kelvin. With a skirt selectivity of 1. 53 (=BW1 dB/BW-28 dB) and low insertion loss this filter is an excellent candidate for suppressing contiguous spurious signals in cooled low-noise receiving front ends.
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Physics and Astronomy (miscellaneous)