MODELING A DECAMETER RADIO LINK IN PREDICTING THE RELIABILITY OF COMMUNICATION

Представлено краткое описание последовательности расчета надежности связи в декаметровом диапазоне волн, включающее в себя ряд методик и моделей определения характеристик условий распространения радиоволн и технических параметров элементов радиолинии. Особенностью предлагаемой модели декаметровой радиолинии является системное построение методик и алгоритмов определения параметров радиолинии для единой задачи прогнозирования условий радиосвязи, имеющей целью создание адаптивной радиолинии нового типа - с учетом параметров изменений геомагнитной возмущенности. A brief description of the sequence of calculation of communication reliability in the decameter wave range is presented. It includes several methods and models for determining the characteristics of radio wave propagation conditions and technical parameters of radio link elements. A feature of the proposed decameter radio line model is the system construction of methods and algorithms for determining radio line parameters for a single problem of predicting radio communication conditions, which aims to create an adaptive radio line of a new type - taking into account the parameters of changes in a geomagnetic disturbance.

Method for the synthesis of broadband devices with an optimal characteristic of the power conversion factor, matching the time-varying load impedance.

A method is proposed for the synthesis of broadband matching devices that adapt radio engineering systems to the changing load impedance in a wide range of natural conditions of their operation. The results of experimental studies of the effect of operating conditions on the impedance of VHF and UHF radio antennas with matching devices are presented. An invariant of the sensitivity of the reflection coefficient function to changes in the load impedance is obtained, on the basis of which a complex criterion for the synthesis of broadband matching devices is developed. A broadband matching circuit was synthesized for the AD-44/CW-TA-30-512 antenna device, which provides a gain in the potentially achievable radio line range of up to 5% in relation to the standard matching device. An analytical mathematical model of a broadband matching device is developed and based on it, a matching device adaptive to the changing impedance of the AD-25/CW-3512 antenna is synthesized, providing an average gain in the potentially achievable range of the radio line from 2% to 15% in the framework of the presented experimental studies.

Refined method for determining the spatial correlation interval of the fading in a single-beam decameter radio link.

In this articlea a refined method have been developed for determining the spatial correlation interval for fading in a decameter radio link with one discrete beam (mode), which are caused by wave diffraction on small-scale ionospheric irregularities. A refined dependence of the spatial correlation interval of fading in a single-beam decameter radio line on the parameters of small-scale ionospheric irregularities, the equivalent length of the radio line and the choice of the operating signal frequency through the value of the root-mean-square deviation of fluctuations of the wave phase front at the output of the inhomogeneous ionosphere is obtained. It is shown that under conditions of disturbances (diffuseness) of the ionosphere, as well as the approach of the operating frequency of the radio line to the maximum applicable frequency, when fluctuations of the phase front of the wave at the output of the ionosphere exceed 1.25 radians, the well-known simplified expression for estimating the interval of spatial correlation of fading can be used in a single-beam decameter radio links with an error of no more than 5%.

Methodology for assessing the range of reception by modern telemetric means when launching products from cosmodromes

Проведен анализ места размещения измерительного пункта с точки зрения получения полного объема телеметрической информации при пусках изделий с заданного космодрома. Методика оценки дальности приема основана на расчёте зон радиовидимости стационарных измерительных пунктов по трассе выведения с учетом угловой ориентации изделия в ходе полета, расчёте энергетического запаса радиолиний для существующих и перебазируемых средств приёма телеметрической информации, оценке потерь уровня сигнала в радиолинии, проверке отсутствия экранирования радиолинии факелом двигателя. The analysis of the location of the measuring point from the point of view of obtaining the full volume of telemetric information when launching products from a given cosmodrome is carried out. The method for assessing the reception range is based on calculating the radio visibility zones of stationary measuring points along the injection route, taking into account the angular orientation of the product during flight, calculating the energy reserve of radio lines for existing and relocatable means of receiving telemetry information, assessing the signal level loss in the radio line, checking the absence of shielding of the radio line by the engine torch.