Wide-band dielectric filter at C-band manufactured by stereolithography

In this paper, an original solution for dielectric wide bandpass filters is introduced. A 4-pole filter based on the TM
_01δ
mode has been designed in a single piece including resonators and coupling elements. The dielectric part is based on a high permittivity material (Zirconia) and has been manufactured using additive manufacturing technology (stereolithography). The breadboard shows a Q-factor around 1100, 5% bandwidth at 4GHz with insertion losses of 0.25dB and an in-band return loss of -9dB. The introduction of dielectric material for wide bandpass filters provides a reduction size which a key drivers for space applications.