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Документ A method of protecting information in cyber-physical space(Національний технічний університет "Харківський політехнічний інститут", 2023) Dzheniuk, Nataliia; Yevseiev, Serhii; Lazurenko, Bogdan; Serkov, Oleksandr; Kasilov, OlegThe subject of the study is the processes of ensuring the reliability and security of information in cyber-physical space. The objective is to develop recommendations for the implementation of a method of information security in cyber-physical space. The development is based on the technology of ultra-wideband signals circulating in wireless communication channels. The task is to ensure the stable and reliable operation of the airborne wireless mobile communication network, which is the main component of cyberspace and its most vulnerable link to destructive influences. Methods used: methods of analytical modelling and time-position pulse coding. The following results were obtained. It is shown that in order to ensure high quality of wireless network operation, it is necessary to expand its bandwidth, which is limited by the physical resource of the radio frequency spectrum. It is proposed to overcome this contradiction by applying the technology of ultra-wideband signals, the base of which is much larger than one. In this case, the information signal is emitted without a carrier frequency simultaneously in the entire frequency band, provided that the signal level is lower than the noise level. The method of positional-time coding is used, in which each information bit is encoded by hundreds of ultra-short chip pulses arriving in a certain sequence. In such wireless communication systems, the use of autocorrelation reception of modulated ultra-wideband signals is proposed. A comparative analysis has shown that the wireless network with the best reliability and noise immunity is the one where the time separation of the reference and information signals is applied. During the first half of the bit interval, the switch closes the transmitter output directly to the ultra-wideband signal generator, forming a reference signal. In the middle of the bit interval, the switcher switches the output to one of two possible positions depending on the signal "zero" or "one", forming the information part of the signal. Conclusions. Systems with autocorrelation reception and separate transmission of reference and information signals provide a high level of structural signal concealment, as well as reliable transmission of digital information, especially in conditions of interference.Документ Excitation of own oscillations in semiconductor components of radio products under the exposure of third-party electromagnetic radiation(Національний технічний університет "Харківський політехнічний інститут", 2022) Serkov, Aleksandr; Breslavets, Vitalii; Breslavets, Juliya; Yakovenko, IgorThe subject matter is the processes of analysis and mechanisms of interaction of EMP-induced currents and voltages with the processes characterizing the functional purpose of radio products, is usually carried out within the framework of the theory of distributed circuits. The presented approach makes it possible to evaluate the performance criteria in general (for example, to evaluate the critical energy characterizing a thermal breakdown), however, issues related to the determination of various types of electromagnetic interactions that occur directly in the components of a product under the influence of EMR remain open. The aim is the possibility of setting up theoretical and experimental studies based on the proposed calculation model for excitation of natural vibrations of a semiconductor structure (exponential growth of amplitude). The parameters of a third-party pulsed electromagnetic field, induced currents and characteristics of semiconductor devices have been established within which the regime of amplification of natural vibrations of a semiconductor structure is observed. The objectives are: mechanisms of interaction of induced currents with surface vibrations of semiconductor components of a radio product under the influence of pulsed electromagnetic radiation. The methods used are: methods of the theory of small perturbations in determining the spectrum of natural oscillations of the system - currents induced by electromagnetic radiation and natural oscillations of the components of the radio product. The following results are obtained: The mechanisms for the appearance of reversible failures of semiconductor components of radio products under the influence of third-party pulsed electromagnetic fields are determined. It has been established that the presence of a current induced by external radiation leads to the establishment of a mode of amplification of natural oscillations of semiconductor components of a radio product (reversible failures). Conclusion. Quantitative estimates of amplification (generation) modes of oscillations of semiconductor devices, distorting their performance depending on the parameters of external electromagnetic influence, allows developing mechanisms for electromagnetic compatibility of microwave radio products. A comparative analysis of the calculated data obtained in the work can be used in the manufacture of radio devices operating in the millimeter and submillimeter range (amplifiers, generators and frequency converters).