Coupling coefficient of quarter-wave resonators as a function of parameters of comb stripline filters

The relationship of the coupling coefficient of quarter-wave resonators operating on the main resonance frequency f0 as a function of different parameters of comb filters made of sections of symmetric striplines has been analyzed. It has been found out that the coupling coefficient increases with the rise of relative dielectric permittivity of striplines, their thickness and the resonance frequency. The measured characteristics of the stripline 4-resonator comb filter with central frequency f0 = 2.4 GHz built on dielectric material with εr = 9.7 are also presented