High-frequency band-pass filter having multiple resonators for providing high pass-band attenuation

摘要

A high-frequency band-pass filter has an input resonator, a middle resonator and an output resonator which are coupled in parallel. The input resonator and the output resonator are capacitively shortened quarter-wave line resonators. To improve the attenuation characteristics, the middle resonator is designed as a capacitively shortened half-wave resonator. The input resonator extends along a first part of the length of the middle resonator. The output resonator extends along a second part of the length of the middle resonator.