Abstract

In current research, new method of automated demodulation of amplitude modulated multichannel signals transmitted with unknown parameters has been proposed and tested. The method is perspective and actual because demodulation is an ill-posed problem when both the carrier and envelope signals are broadband and unknown. The innovative point of this study is the elaboration of the method that enables the evaluation of unknown parameters of the AM signal. The method is based on a new approach called the 3D spectrum representation of AM signals, where the first dimension indicates the allocation of carrier frequencies, the second indicates the band of message signal and the third is related to time. In this study, we report that the 3D representation enables to track unknown AM signal parameters, such as the carrier frequency, frequency of message signal and number of channels and apply demodulation techniques even for time-varying parameters of the signal. The results of the performed experiments indicate that the proposed method effectively performs the envelope detection and automated demodulation of multichannel AM signals.

Keywords:

Amplitude modulation, carrier, demodulation, envelope, inference,

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Competing interests

The authors have no competing interests.

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