Microstrip filters based on counter-comb structures with additional galvanic connection

This paper examines the design principles of microstrip filters (MSF) with increased frequency selectivity based on compact structures with a limited number of quarter- wave resonators. It is shown that in three-resonator three-step comb structures, it is possible to form three working attenuation poles at finite frequencies. The conditions for creating on the basis of these structures highly selective multiresonator microstrip filters with the number of working attenuation poles equal to the number of resonators in MSF are given.