MODELING OF TWO MICROSTRIP FILTERS OF THE CENTIMETER RANGE

Abstract

Band-pass filters are an integral part of any radio equipment. They determine the selectivity of the receiver for all channels of reception. The aim of this work is to modelling two microstrip filters of the centimeter wave range. The object of study in this work are two microstrip filters at a frequency of 5.75 GHz and 4.6 GHz. Such filters can be used in the converter of the centimeter wave range as a signal and heterodyne filters. Two filters were simulated in the Microwave Office environment. The results are presented in the form of models of two filters and four amplitude-frequency characteristics. Given are the geometric dimensions of the filters, sufficient for their manufacture on material RT5870 of Rogers company. Filters have a bandwidth of 200 MHz and a loss in bandwidth of not more than 3 dB. Losses in the stop band for the signal filter were at least 45 dB, and at least 35 dB for the heterodyne filter, which is a very good result for a two-pole filter. Acceptable electrical parameters, small dimensions and moderate cost of manufacturing filters allows them to be widely used in professional and amateur radio equipment. To improve the manufacturability of manufacturing, a material with a low dielectric constant was selected. At the same time, gaps and tolerances on theaccuracy of their manufacture are acceptable. The design of the filters allows them to be easily integrated with other components of the converter: a low-noise amplifier, a mixer, an intermediate frequency amplifier, an amplifier in the local oscillator path.