The algorithm for suppressing tactical radiostations with frequency-hopping spread spectrum (FHSS) was developed. The effectiveness impact of polyharmonic unmodulated interference on the radiotransmission of a radio station with FHSS was estimated.

The mathematical analysis of the probabilistic characteristics of signals transmitted through compressed communication channels with orthogonal frequency separation in the presence of fading in the communication channel obeying the Nakagami-m distribution law is carried out in the paper. In contrast to previous studies, the effect of a non-uniform distribution of the fading phase in a communication channel on the probability of signal reception errors is examined. A unified mathematical expression of the generating function of moments is presented for the fading coefficients in the communication channel in the frequency domain, distributed in accordance with the Nakagami-m law with non-uniform phase distributions. Thus, the classical methods for determining the generating function of moments can be directly used to determine the exact mathematical representation of the probability of error receiving signals for various types of modulation and diversity of signals.

The new effective methods and algorithms were developed for generating of program trajectories for robotic manipulators of arc welding with account of technological limits. The proposed methods and algorithms, in contrast to the known ones, allow to effectively take into account the shape of the welded seam, as well as the constraints imposed on its orientation. The effectiveness of the developed methods and algorithms is confirmed by the results of experiments with models of robot-manipulators.

The parametrically adjusted hyperspectral data compression algorithm based on wavelet decomposition is presented. Data stream compression throughput assessment depending on wavelet decomposition level is carried out, the overall performance of the presented algorithm is estimated.

The thermal expansion of single crystals of solid solutions (MnIn₂S₄)_1–х•(AgIn₅S₈)_х was measured by the dilatometric method in the temperature range 80–450 K. The coefficients of thermal expansion are determined and their concentration dependences at different temperatures are constructed. It is established that the indicated quantities with composition x vary linearly. From the obtained values of the coefficients of thermal expansion, the Debye temperatures and the mean-square dynamic displacements of the atoms are calculated. It is shown that as the temperature is raised, the Debye temperature decreases, and the mean square dynamic displacements of the atoms increase.

To generate high-power microwave oscillations it is proposed to use an O-type backward-wave oscillator (BWO) with an electrodynamic system on folded rectangular waveguides. The mathematical model uses sheet electron beams. The space charge is taken into account. Optimization calculations have been carried out and optimal generator efficiencies have been obtained for different sizes of electron beams, accelerating voltages 400–500 kV, currents 200–900 A. The analysis of interaction processes has been carried out. To increase the power of the generators proposed two-section scheme. Calculations showed, that the electronic efficiency of irregular relativistic BWO reaches 30–42 %, the output power is 50–170 MW.

The paper presents the results of studies of heat fluxes in a printed circuit board made of aluminum with nanoporous anodic alumina, generated by linear heat source. It is established that in this case the shape of the cone of the heat pipe with the beginning from a point heating source on the surface was characterized by expansion towards the back side of the aluminum base. This effect leads to a decrease in the thermal resistance of the printed circuit board.

It's proposed to modify the consist and electromagnetic radiation shielding properties of powdery activated carbon by the method of chemical deposition of copper clusters on the surface of fractions of such material. The choice of these element caused by it resistance to the environment conditions, which could determines the stability of the shielding properties of materials including of these elements. Regularities of electromagnetic radiation interaction with powdery activated carbon modified by the proposed method were researched. According to the results of this research it's established that electromagnetic radiation reflection coefficient in frequency range 8…12 GHz of shields made with powdery activated carbon decreases from –2 to –14 dB after modification of such material consist.

It's considered the way in which the method of a cylindrical rod together with a vector network analyzer is used to determine the dielectric constant. The algorithm for determining the dielectric constant is developed. Dependences of the dielectric constant of textolite and fluoroplastic on the frequency in the range 25.95–37.5 GHz are investigated.

The results of studying of the impact of formation modes of platinum silicide using qiuck heat treatment on electrophysical parameters of Schottky diodes are presented. It is shown that this treatment, as compared to the traditional one, allows at the cost of reducing of microrelief of boundary of PtSi–Si, and also obtaining as a result of treatment a less defective and equilibrium structure of the barrier layer, to raise barrier height from 0,804 to 0,825 V, to reduce leakage current from –4,42·10^-6 to –2,85·10^-6 A and in 1,25 times and to raise the reliability of Schottky diodes at operating temperature 125 °C.

A novel measurement method for repetition frequencies of the blades of an aerial vehicle (in part, helicopter's main and tail rotor) for adaptation circuits of the radar sensor with an inverse synthesis of antenna aperture is proposed. The method based on the convolution of the spectrum of the «secondary» modulation of the signal with simultaneous compensation of the Doppler frequency of the reflected signal. This allows in typical conditions for the radar sensor rapid change of Doppler frequency to provide a long coherent accumulation and, accordingly, high accuracy of measurement of the rotational frequencies of the rotors.

The article presents the results of numerical simulation of a spherical array synthesized taking into account the polarization properties of the emitters. The formation of a directional diagram of a spherical array with different width of the main lobe and the required levels of the cross-polarization component and side lobes is considered. The article also presents the results of the formation of directional diagrams of a spherical array with the required level of cross-polarization component and a given width of the main lobe at different levels of the side lobes.

ZnO thin films of zinc oxide doped with 10 % ITO (indium tin oxide) on anodic aluminum oxide substrates are formed in vacuum during high-frequency repetitively pulsed laser deposition. The morphology of films on porous and non-porous surfaces of substrates was studied by atomic force microscopy. The optical properties of the films in the visible, near, and middle IR regions of the electromagnetic radiation spectrum, the Raman spectra, and also the features of the photoluminescence characteristics have been experimentally investigated. Zinc oxide films can be used in optoelectronic transducers, as luminescent material, in the form of transparent electrodes, sensitive layers of gas and biological sensors, catalysts, X-ray and gamma-radiation detectors.

It is shown necessary taking into account the clinotron electron radiation while running into the surface of slow-wave structure. The formulas E_q, H_j of the total clinotron electron radiation for the nonrelativistic version are presented.