Experimental study of band pass filters based on multilayer technology

Frequency-selective microwave devices are an integral part of the antenna-feeder path of radar and radio navigation systems, and other infocommunication systems. Band pass filters are the most widely used in these systems. They provide primary selection of a useful signal mixed with noise. A promising direction in the design of microwave band pass filters is their multilayer design using strip and slot resonators. At present, such a design of microwave band pass filters has not been fully investigated. Purpose of the study. The purpose of this paper is an experimental study of band pass filters based on the multilayer strip-slot technology of their design. At the same time, their amplitude-frequency characteristics, including the reflection coefficient and the transmission coefficient in the frequency range, are subject to experimental study. Materials and methods. The computer simulation of band pass filters was carried out in electrodynamics simulation program, where the main geometric dimensions of the filter topology elements were selected and their amplitude-frequency characteristics were preliminary studied. At the same time, a feature of the studied band pass filters is the use in their design of domestic microwave material based on fluoroplast layers - FAF-4D, which corresponds to the import substitution program. Based on the results of computer simulation, prototypes of band pass filters were made and their experimental study was carried out using a vector network analyzer in the frequency range up to 2 GHz. Results. According to the results of the experimental study, a good qualitative and quantitative agreement between theoretical and experimental data was determined. Thus, the maximum deviation of the gain amplitude value obtained from the results of computer simulation from the experimental results is no more than 0.53 dB; the maximum deviation of the bandwidth limits is no more than 30 MHz (3% relative to the center frequency). Conclusion. The results of the experimental study prove the possibility of developing and using microwave band pass filters based on multilayer strip-slot technology.