Title :
Theory of digital phase shifters based on high-Tc superconducting films
Author :
Vendik, Irina B. ; Vendik, Orest G. ; Kollberg, Erik L. ; Sherman, Vladimir O.
Author_Institution :
Dept. of Radio Eng., Electrotech. Univ., St. Petersburg, Russia
fDate :
8/1/1999 12:00:00 AM
Abstract :
A theory of digital phase shifters based on transition from a superconducting (S) state into a normal (N) state in high-Tc superconductor (HTS) films is developed. It is shown that the insertion-loss level in the phase shifters is determined by the commutation quality of the HTS film and does not depend on the S-N switching element shape and size. The procedure for designing the S-N phase shifter with minimum insertion loss is equivalent to designing a matching circuit for the termination Z=√RSRN (RS and RN are the resistances of the switching element in the S- and N-states, respectively). Different versions of S-N phase shifters are suggested and discussed. High-quality S-N phase shifters can be successfully designed in a 1-10 GHz frequency range and find application on the receiving end of microwave systems
Keywords :
Q-factor; high-temperature superconductors; losses; microwave phase shifters; microwave switches; superconducting microwave devices; superconducting switches; superconducting thin films; 1 to 10 GHz; HTS film; HTSC; S-N switching element; commutation quality; digital phase shifters; high-Tc superconducting films; insertion-loss level; microwave operation; Frequency; High temperature superconductors; Insertion loss; Phase shifters; Superconducting device noise; Superconducting films; Superconducting filters; Superconducting microwave devices; Switches; Thermal conductivity;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
