Analysis of the experience of modern armed struggle shows that timely detection of signals onboard radio sources by radio monitoring systems is an important task. One way to ensure its solution is the use of compact broadband antennas in the centimeter range. Therefore the development and improvement of methods for calculating broadband compact antennas in the centimeter wave range is an important and relevant scientific and practical task. An improved method for calculating a traveling wave antenna based on irregular symmetrical slit lines located arranged on a multilayer dielectric substrate (Vivaldi antennas) is proposed, by taking into account the thickness of the dielectric substrate, the relative effective dielectric constant of the substrate layers and two-way power supply to improve the directional properties of the antenna and its coordination in a given frequency band. In particular, the formulas of the phase multiplier of the system (for two radiating elements) and the resulting pattern of the antenna take into account the two-way power supply and the thickness and relative dielectric constant of the substrate. These advanced formulas for calculating and selecting these options antennas, lengths; maximum and minimum slot width; the coefficient of opening the gap; the width of the strip of symmetrical microstrip power line at the connection of the coaxial power line; the width of the strip at the intersection with the slit line; the width of the symmetrical slit line at the base of the opening; the length of a quarter-wave transformer based on a symmetrical microstrip line; the length of the symmetric microstrip power line; slit length; resonator diameter; the radius of the cover of the structural capacitor. The practical significance of the results obtained lies in the possibility of an approximate calculation of compact broadband antennas in the centimeter wavelength range. The results make it possible to model and manufacture these antennas for radio monitoring systems for onboard radio sources.

Analysis of the experience of modern struggle shows that the success of combat missions to sone extent depends on the timely detection of information from communication channels, in particular, radio relay communication lines. Increasing the detection range of the radio monitoring station can be achieved by using a mirror parabolic antenna with a radiation in the form of a conical horn with low losses due to the use of a matching device. The constructive decisions of matching devices are analysed and it is determined that most of them are resonant. The substantiation and selection of the design of the dielectric transformer with the length ( – wavelength in a round waveguide, m) for coordination of the conical horn irradiator in the whole band of its operating frequencies for the wave type is carried out. To achieve the goal, the methods of antenna theories and electrodynamics were used, in particular the theory of long lines. A mathematical apparatus has been developed for calculating the parameters of a dielectric transformer (the length ). It is stated that its impedance must be equal to the modulus of load resistance. The calculation of the value of the active transformed resistance according to the formula (10) always gives a positive value of the input resistance, the value of which is greater the greater the reactive load reactance. The reliability of the obtained formulas is confirmed by the convergence of units and graphs of dependences of the changes of the outer radius of the coaxial power line (its impedance), as well as the thickness and place of inclusion on the matching dielectric transformer . The practical significance of the research results lies in the possibility of improving the matching of a horn antenna based on a circular waveguide in the range of its operating frequencies for a certain type of wave.