V.G. Kartashevsky1, E.S. Semenov2, V.A. Cymbal3

1 Povolgsky State University of Telecommunications and Informatics (Samara, Russia)

2 Volgograd State University (Volgograd, Russia)

3 Branch of the Military Academy of the RVSN named after Peter the Great (Serpukhov, Russia)

1 vgkartash@ya.ru; 2 essemenov@mail.ru; 3 tsimbalva@mail.ru

The paper investigates the ways of organizing FHSS communication system using OFDM signals under the conditions of the measured parameters of the channel used. It is assumed that "protective gaps" are not used in the structure of the group signal FHSS technology. A variant of the formation of the OFDM symbol structure with a "test combination" is considered, the knowledge of which allows the regularization method to solve the problem of estimating the samples of the impulse response of the communication channel with memory. In this case, estimates are obtained from solving a system of algebraic equations, the order of which is determined by the size of the channel memory.

To solve the problem of demodulating the signal from the "working package" of the OFDM symbol, estimates of the envelope counts of this part of the OFDM symbol are formed, according to which decisions on the transmitted discrete symbols are recorded at the output of the FFT calculation unit.

Data on computer modeling of the problems under consideration are presented, the results of which confirm the possibility of using the proposed solutions for special purpose networks.

Kartashevsky V.G., Semenov E.S., Cymbal V.A. The use of OFDM signals in pseudorandom tuning of the operating frequency technology (FHSS). Radiotekhnika. 2024. V. 88. № 2. P. 118−126. DOI: https://doi.org/10.18127/j00338486-202402-15 (In Russian)

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