I.S. Faustov1, A.B. Tokarev2, V.A. Kozmin3

1, 2 FSBEI of HE “Voronezh State Technical University” (Voronezh, Russia)

1-3 JSC “IRCOS” (Moscow, Russia)

1 faustov.97@bk.ru; 2 tokarevab@ircoc.vrn.ru; 3 kozminva@ircos.ru

Formulation of the problem. Radio monitoring of short-range systems is often complicated by the presence of fading due to the complex interference pattern at the receiving point. An effective method of combating fading is a diversity combining. Standard methods of diversity combining require an estimate of the amplitude multiplier and (or) phase shifts when adding signals, which significantly complicates the procedure of spaced reception.

The aim of the work is to explore the possibilities of a diversity combining without the need to estimate a complex channel multiplier.

Results: the possibility of providing high noise immunity without the need to estimate the radio channel profile for signals with Gaussian frequency-shift keying (GFSK) in conditions of slow flat fading is demonstrated. A method has been developed for receiving GFSK signals, which makes it possible to combine two or more receiving channels to increase noise immunity in multipath conditions.

Practical significance. The presented method has a relatively low computational complexity and makes it possible to increase the efficiency of radio monitoring systems.

Faustov I.S., Tokarev A.B., Kozmin V.A. Implementation of diversity combining for radio monitoring of frequency-modulated signals. Radiotekhnika. 2024. V. 88. № 7. P. 26−30. DOI: https://doi.org/10.18127/j00338486-202407-05 (In Russian)

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