A.S. Orlova1, S.B. Makarov2, S.V. Zavjalov3, S.V. Volvenko4

1-4 Peter the Great St. Petersburg Polytechnic University (St. Petersburg, Russia)

1 ovsyannikova_as@spbstu.ru; 2 makarov@cee.spbstu.ru; 3 zavyalov_sv@spbstu.ru; 4 volk@cee.spbstu.ru

Formulation of the problem. In an industrial scenario, indoor wireless data transmission is characterized by a high degree of multipath propagation caused by reflection from various stationary objects, walls, partitions, stairs, etc. Such transmission channels, as a rule, are not described by known multipath propagation models. To improve the quality of receiving messages in such conditions, equalizers are used to partially compensate for the intersymbol interference caused by multipath propagation. With the known nature of this interference, additional gains can be obtained if optimal signals based on long-duration amplitude pulses are used in such transmission channels.

Goal. Solving the problem of synthesizing optimal signals that provide a smaller error vector magnitude (EVM) in conditions of multipath propagation.

Results. A procedure for synthesizing optimal signals is proposed and implemented to obtain a reduction in the EVM under multipath propagation conditions. The optimization constraints include the constraint on the correlation coefficient of signals and the constraint on the level of EVM. The shapes of optimal amplitude pulses and energy spectra of random sequences of signals based on these pulses are obtained. It is shown that the use of optimal signals makes it possible to reduce by 3 times the ratio of the level of the useful signal at the output of the equalizer to the level of intersymbol interference associated with multipath propagation of radio signals compared with the case of using signals based on RRC pulses.

Practical significance. The new optimal signals obtained in the work can be used for indoor wireless data transmission in industrial scenario.

Orlova A.S., Makarov S.B., Zavjalov S.V., Volvenko S.V. Optimal signals for multipath data transmission channels. Radiotekhnika. 2025. V. 89. № 3. P. 121−134. DOI: https://doi.org/10.18127/j00338486-202503-11 (In Russian)

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