M.A. Romashchenko1, D.V. Vasil’chenko2, R.S. Sukhomlinov3, N.V. Astahov4, O.Yu. Makarov5

1-4 FSBEI of HE “Voronezh State Technical University” (Voronezh, Russia)

1 kipr@vorstu.ru; 2 shadow951@bk.ru; 3 sukhomlinov03@mail.ru, 4kipr@vorstu.ru

Formulation of the problem. As the number of wireless devices operating in unlicensed frequency bands increases, the radio-frequency spectrum becomes more congested, which leads to stronger mutual interference and degraded communication quality. In LoRa networks, this problem is further aggravated by the fact that transmission robustness and channel utilization efficiency are largely determined by the modulation parameters, primarily the spreading factor and signal bandwidth. Under these conditions, the problem of determining the modulation parameters of the received signal becomes important both for the design of interference-resistant communication channels and for spectrum monitoring and electromagnetic environment analysis.

Purpose. To review current methods for determining the modulation parameters of LoRa signals, with emphasis on spreading factor estimation under different reception conditions.

Results. A review of current methods for determining the modulation parameters of LoRa signals under different reception conditions was carried out. It is shown that the existing approaches can be divided into three main groups: methods for preliminary estimation of modulation parameters at the receiver side; methods for parameter estimation from a pre-isolated signal using artificial intelligence; and methods for wideband data processing aimed at analyzing multiple simultaneous transmissions. It was established that the use of the preamble is the most appropriate approach for preliminary estimation of signal parameters, whereas for methods based on the analysis of a pre-isolated signal, the choice of the most informative signal representation is of major importance.

Romashchenko M.A., Vasil’chenko D.V., Sukhomlinov R.S., Astahov N.V., Makarov O.Yu. Current approaches to the evaluation of modulation parameters of Long Range (LoRa) radio signals // Radiotekhnika. 2026. V. 90. № 7. P. 13−17. DOI: https://doi.org/10.18127/j00338486-202607-02

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