O.B. Popov1, T.V. Chernysheva2, K.A. Korostelev3, P.S. Sapronov4

1–4 Moscow Technical University of Communications and Informatics (Moscow, Russia)

1 olegp45@yandex.ru, 2 krba2012@yandex.ru, 3 kirill19990511@yandex.ru, 4 pavelozone@gmail.com

It is generally accepted to measure the frequency response (FR) of the transmission ratio (TR) of the sound broadcasting channel paths by changing the harmonic sinusoidal signal in it. Intelligent audio processor systems for processing the sound broadcasting signal (SBS) and its compact representation are widely used in all channel paths, which change the properties of the SBS and TR, in-creasing the "preference" of the signal for the listener. As a result, the TR formed by the sinusoidal signal and the TR during transmission of the real SBS do not coincide. Measuring the TR by the real signal was hampered by the lack of spectral analysis algorithms that were close in accuracy to the capabilities of the human auditory analyzer. Original spectral analysis methods developed by the authors allow increasing their accuracy and resolution, which makes it possible to monitor the FR of paths directly during transmission of the audio program for all devices included in the channel.

The authors propose to form the FR of the SBS transmission channel and its component paths on a real SBS, which allows taking into account the features of audio processing, compact representation and transmission of the SBS.

A technique for measuring the frequency response using a real signal is proposed, which allows avoiding the degradation of the SBS in the transmission channel paths. An original algorithm for spectral analysis of the SBS with an accuracy and resolution close to the accuracy of the human auditory analyzer is developed. Distortions in the frequency response are revealed that appear only when transmitting a real SBS and reduce the quality of transmission for the listener.

The measurements carried out using the developed algorithm on real signals, including in the SBS transmission channels, confirmed the possibility of forming an objective assessment of the FR changes and their correction.

Popov O.B., Chernysheva T.V., Korostelev K.A., Sapronov P.S. Measuring the real transmission coefficient of a sound broadcasting channel. Electromagnetic waves and electronic systems. 2025. V. 30. № 6. P. 5−15. DOI: https://doi.org/10.18127/j15604128-202506-01 (in Russian)

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