L.I. Averina1, O.K. Kamentsev2

1,2 JSC «Concern «Sozvezdie» (Voronezh, Russia)

Currently, broadband radio access systems most commonly use orthogonal frequency division multiplexing (OFDM) technology. However, the performance available in current generations of wireless networks thanks to OFDM technology is no longer sufficient to meet the high demands of next generation networks. One of the contenders for them are spectrally efficient signals with frequency multiplexing. The main disadvantage of such signals is the violation of the orthogonality of the subcarrier frequencies, which greatly complicates the implementation of the detection process and degrades the noise immunity of the system. The paper proposes a set of algorithmic approaches that allow not only to reduce the amplification of the conversion noise when detecting spectrally efficient signals with frequency multiplexing, but also to effectively deal with the emerging intersymbol interference. On the basis of simulation modeling, a comparative analysis of the noise immunity of communication systems in a channel with white Gaussian noise using the technology of orthogonal and spectrally efficient frequency multiplexing under various conditions was carried out.

Averina L.I., Kamentsev O.K. Improving the spectral efficiency of signals with frequency multiplexing in high-speed communication systems. Radiotekhnika. 2023. V. 87. № 5. P. 115−122. DOI: https://doi.org/10.18127/j00338486-202305-12 (In Russian)

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