A MATHEMATICAL MODEL OF THE SIGNAL REFLECTED FROM AIR TARGETS WITH A TURBOJET ENGINE

Currently one of the urgent tasks in radar is the task of the recognition of air targets. At the decision of tasks of synthesis and analysis of radar recognition systems it is necessary to use a mathematical model of the reflected signal. Therefore, developed and justified mathematical model of the signal reflected from air targets with a turbojet engine based on the geometric features of the engine, taking into account the spectral components of the secondary modulation caused by reflection from the steps of compressor (turbine) lowpressure engine. Implementation of the mathematical model obtained based on the effect the secondary modulation when using modulation features. The mathematical model of the reflected signal allows to represent the spectral-Doppler portrait of the aerial target, which takes into account the distribution of the amplitude and phase matching of all components present in the spectrum of the reflected signal. Also allows us to investigate design features of turbojet engines due to the number of blades in the turbine stages and their geometric dimensions, shaft speed, compressor as well as engine size. In the developed mathematical model shows the dependence of the effect of different wavelength of radiation the possibility of its application to radar recognition of air targets such as «aircraft with turbojet engine».

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