Abstract
This paper proposes a new type of comb-line filter suitable for miniaturization utilizing stratifying technology. The filter consists of a couple of quarter-wavelength resonators. Each resonator is composed of two sections of CPW (coplanar waveguide) and MSL (microstrip line) which is fabricated on the other side of the CPW. Both sections are connected to each other with a piece of bonding wire at an open end to set up a new type of folded comb-line filter. The filtering characteristics are investigated through experiments as well as numerical simulations by means of the FD-TD method. It is shown that the filtering characteristics are improved by adjusting coupling between the resonators. It is also shown that the filter can be miniaturized by introducing stepped impedance structure in the resonators.
