Conception and realization of highly selective bandpass filters in Ka-band built on thin polymer films
Résumé
A novel structure of high performance narrow bandpass
filters on thin polymer film is reported in this paper. It’s
composed of two microstrip resonators placed between two viafree
microstrip–grounded coplanar waveguide transitions. It
combines therefore compactness, low-cost, fabrication easiness of
microstrip lines and connection facility of coplanar pads. Narrow
band-pass filters have been optimized by using HFSS software,
realized and characterized, over the range of Ka-band
frequencies. With the band-pass filter realized on thin BCB
polymer (benzocyclobutene, relative permittivity er = 2.65 and
loss tangent tanδ = 0.0025) film of 60 μm thick, the performance
obtained for a center frequency optimized at 30.5 GHz is 28.8 for
quality factor and -1.4 dB for insertion losses, with very good
agreement between simulation and experiment results.