A.N. Vereshchagin1, A.A. Abdulhakov2, M.M. Valihanov3, K.R. Plykin4

1-4 Siberian Federal University (Krasnoyarsk, Russia)

4 JSC «NPP «Radiosviaz»

1 AVereshagin@sfu-kras.ru; 2 AAbdulkhakov@sfu-kras.ru; 3 MValikhanov@sfu-kras.ru; 4 Kplykin@sfu-kras.ru

Currently, simulators of navigation signals are used to verify and calibrate the equipment of consumers of global satellite navigation systems. The accuracy of calibration of navigation signal simulators is influenced by many factors, one of which is systematic error caused by impedance mismatch in the signal transmission path. As a rule, to eliminate this error, an additional attenuator is used at the end of the transmission line, but in this case it will be necessary to increase the power of the generated signal, which is not always possible. If the impedances are not matched, reflected signals will occur in the transmission line. Only the first one is of greatest interest - since it will have the highest energy. Therefore, the signal that the navigation signal simulator generates at the input of a digital oscilloscope can be considered as the sum of two: the main one and the first reflected one. Therefore, the work proposes a method for combating multipath - MEDLL. Simulations were carried out for various levels of the reflected signal. The results obtained confirm the possibility of using MEDLL to combat reflections in the signal transmission line and thereby make it possible to reduce the error in measuring the radio navigation parameters of the signal generated by the navigation signal simulator in the range from 5% to 99.9%.

Vereshchagin A.N., Abdulhakov A.A., Valihanov M.M., Plykin K.R. The method of compensation of impedance mismatch effect in the signal transmission path when measuring delays of navigation signal simulators by digital oscilloscope. Radiotekhnika. 2024. V. 88. № 4. P. 83−89. DOI: https://doi.org/10.18127/j00338486-202404-08 (In Russian)

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