Title :
A Wideband HTS Planar Microwave Balun
Author :
Xueqiang Zhang ; Xiaofeng He ; Yusheng He
Author_Institution :
Nat. Lab. for Supercond., Inst. of Phys., Beijing, China
Abstract :
This paper presents a high-temperature superconducting (HTS) planar balun. The balun exhibits an excellent amplitude and phase balance performance. The balun was fabricated using double-sided HTS YBCO films on a 0.5-mm-thick 3-in LaAlO3 substrate. The balun demonstrates a wideband operation and a low insertion loss. The center frequency of the balun is 1.25 GHz. The return loss bandwidth of 18 dB is 1.02 GHz (the fractional bandwidth is 82%). The phase imbalance is less than 7. The amplitude imbalance is less than 0.7 dB, and the insertion loss is less than 0.31 dB over 0.69-1.77 GHz.
Keywords :
UHF circuits; baluns; high-temperature superconductors; microwave circuits; superconducting devices; LaAlO3; bandwidth 1.02 GHz; double-sided HTS YBCO film; frequency 0.69 GHz to 1.77 GHz; high-temperature superconducting planar balun; insertion loss; loss 18 dB; phase balance performance; wideband HTS planar microwave balun; wideband operation; Helium; High temperature superconductors; Impedance matching; Insertion loss; Microstrip; Radio astronomy; Baluns; high-temperature superconducting (HTS); microwave circuits;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2012.2193615
