Disclosed is a high-temperature superconductor low-pass filter for
removing broadband harmonics in a wireless communication system. The
high-temperature superconductor low-pass filter includes a coupled line
section and a transmission line section, in which the coupled line
section is connected in parallel with the transmission line section. The
coupled line section has two microstrip open-stub type parallel stripe
lines stacked on a high-temperature superconductor, and the transmission
line section has one stripe line. Since the high-temperature
superconductor low-pass filter has attenuation poles at a stopband, it
has stopband characteristics to 7-8 times wider than a cutoff frequency.
The high-temperature superconductor low-pass filter can easily remove
sub-harmonics which are inevitably occurred in the wireless communication
system.