System for control the power of an on-board signal generator of an unmanned aerial vehicle

In this paper, the issues of calibration of the transmission coeffi cient of the antenna system of a ground station for monitoring the energy characteristics of signals from global navigation satellite systems are considered. The most commonly used method for calibrating the transmission coeffi cient of large-aperture mirror antenna systems based on solar radio emission is presented, its advantages and disadvantages are described. To eliminate the disadvantages of calibration based on solar radio emission (a limited range of working angles of the site, the need to involve thirdparty data on the spectral intensity of solar radio emission), an alternative approach to calibration based on an artifi cial source of radio emission placed on board an unmanned aerial vehicle is considered. The features of this approach are indicated – the need to work in the near zone of the measured antenna system, as well as the movement of an artifi cial radio source in a plane parallel to the plane of the aperture of the antenna system. A block diagram of the payload of an unmanned aerial vehicle for measurements in the near zone of the antenna system being measured has been developed. The results of a study of the characteristics of the payload signal generator of an unmanned aerial vehicle are carried out. A solution is proposed to eliminate the error in setting the output power of the signal generator (the difference between the nominal and actual signal power) from the measurement results. The necessity of using a control signal power meter and a bandpass fi lter as part of the payload is shown. A subsystem for monitoring the output power of the signal generator has been designed. Payload components have been selected that meet the limitation on weight and size characteristics. The possibility of remotely connecting the operator to the payload equipment of an unmanned aerial vehicle has been implemented. The perspective of the development of the payload layout is described.

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