Microwave Diplexers Based on Two- and Three-Resonators Microstrip Structures

In this work, we investigated the possibility of diplexers` development based on two- and three-resonator microstrip structures implemented on a substrate with a high relative dielectric constant ε
_r
=80 and without short-circuited elements, which determines their high manufacturability. The conditions for the forming of at least two working attenuation poles of the microstrip structures in the frequency regions of adjacent channels are determined. It is shown that the crosstalk attenuation with such a limited number of resonators in each channel filters reaches a level of at least 55 dB.