V.P. Pashintsev, A.F. Chipiga, G.V. Slusarev, A.V. Senokosova

Problem solution of ensuring power reserve in SCS at close placement of the receiver of radio intercept is to reduce the transmission loss due to absorption on the road SCS compared to the intercept route. To do this, suggested to lower the carrier frequency in the direction of the MMES-ES to values f0 = 30...100 MHz that lead to the emergence of Rayleigh FF and application diversity reception for several antennas. The technique of energy systems analysis SCS when placing the receiver near interception, and developed a way to improve it through the use of low carrier frequency f0 = 30...100 MHz and space-diversity reception for several antennas. It-s develop mathematical model of the ionosphere, analytically describes the change in height of the electron density and effective collision frequency of electrons in the ionosphere. It-s develop mathematical model of the communication channel transionospheric establishing analytical dependence of the signal at the input of the receiver at carrier frequency selection, taking into account absorption in the ionosphere. Founded and developed a mathematical model of the ionosphere, which differs from the known into account the spatial fluctuations of the EC in the inhomogeneities of the ionosphere, characterized by their standard deviation. A mathematical model transionospheric communication channel, allowing us to obtain the analytical dependence of the power of the received signal on the choice of the carrier frequency of the light absorption of the waves in the ionosphere and multipath spread it, and the variance of the signal power attenuation factor due to the knowledge base is fully determined by the dispersion of phase fluctuations of the wave front at the exit of the inhomogeneous ionosphere. An analytical dependence of error probability for noncoherent reception of signals from the signal/noise ratio at the input of the receiver, taking into account wave absorption in the ionosphere and the relationship of regular and fluctuation components of the dispersion factor of the wave attenuation due to multipath. Graphic-analytical technique was developed to establish dependence of the probability of error in the reception of signals on the noncoherent multiple antennas on the ratio signal/noise at the input of the receiver, taking into account wave absorption in the ionosphere and the spatial correlation of fading at spaced antennas. To be admissible at the SCS built the error probability plots of the allowed signal/noise ratios of the choice of the carrier frequency using a single reception and diversity of ≥ 4 antennas that allow us to estimate the range of low frequency f = 60...80 MHz rate of energy stealth SCS placement under close intercept of noise immunity on the intercept of satellite communication systems.