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For surveillance over air traffic the system for reception of ADS-B signals was built. For this purpose the antenna, the receiver of ADS-B signals, the decoder were made and the software for computer was installed. Airplanes on a distance up to 160 km and heights up to 12 000 m were observed. This system has small "blind funnel" and allows to trace airplanes practically "over itself". The system is used in educational process and for performance of student's scientific researches.
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Kharchenko et al. (2012) studied this question.
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