A Simpler Realization of Cross-Coupled Top Loaded Coaxial Resonator based Filters

A 10-pole L-band quasi-elliptic band pass filter is designed and developed without any additional arrangement for cross-coupling realization. The filter circuit is based on capacitive top loaded coaxial resonators, which helps in significant filter size miniaturization along with thermal control due to bimetallic (Invar + Aluminum) arrangement of the resonator structure. The top loaded resonator structure also provides wide spurious free range of 4.5*f
0
. Filter simulation and measurement results are presented and discussed in detail.