Старокожев, С. В.Ткач, М. Г.Глущенко, А. О.Даценко, О. О.Чернишов, М. В.Чумак, В. С.2022-05-192022-05-192021S. Starokozhev, M. Tkach, A. Hlushchenko, O. Datsenko, M. Chernyshov and V. Chumak, "Frequency Efficiency Evaluation of Query Airspace Surveillance Systems," 2021 IEEE 8th International Conference on Problems of Infocommunications, Science and Technology (PIC S&T), 2021, pp. 501-505, doi: 10.1109/PICST54195.2021.9772190.978-1-6654-0682-6DOI: 10.1109/PICST54195.2021.9772190https://ieeexplore.ieee.org/document/9772190https://openarchive.nure.ua/handle/document/20342In this work, there was carried out an evaluation of frequency efficiency of both the interrogation signal channel and the response signal channel in case of intra-system and intentional (correlated and uncorrelated), as well as fluctuation interference. The evaluation based on the representation of interrogation radar systems for observing airspace in the form of two-channel systems for transmitting information of interrogation signals and response signals. It is shown that the use of interrogation signals and response signals in the form of an interval-time and positional code leads to the need for a significant receiving path bandwidth expansion of both the aircraft transponder and the interrogating radar system as a whole. This caused by the requirements for obtaining sharp edges of the received signals, which is necessary for decoding them and leads to a significant decrease in the frequency efficiency of the considered information systems and, as a consequence, to a decrease in the noise immunity of both the request channel and the response channel of the considered information systems.enAirspace control systemsSecondary Surveillance RadarIdentification Friend or Foeair traffic controlrequest signalArticle