<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>In this work the problem of characterization of Discrete Fourier Transform (DFT) spectrum of an original complex-valued signal modulated by random fluctuations of amplitude and phase is investigated. It is assumed that the amplitude and phase of signal values at discrete time moments of observations are distorted by adding realizations of independent and identically distributed random variables. The obtained results of theoretical analysis of such distorted signal spectra show that only in the case of amplitude modulation the DFT spectrum of the modulated bounded signal can be similar to the original signal spectrum, although there occur random deviations. On the other hand, if phase modulation is present, then the DFT spectrum of the modulated bounded signal not only shows random deviations but also amplitudes of peaks existing in the original spectrum are diminished, and consequently similarity to the original signal spectrum can be significantly blurred.</p></abstract>

In this work the problem of characterization of Discrete Fourier Transform (DFT) spectrum of an original complex-valued signal modulated by random fluctuations of amplitude and phase is investigated. It is assumed that the amplitude and phase of signal values at discrete time moments of observations are distorted by adding realizations of independent and identically distributed random variables. The obtained results of theoretical analysis of such distorted signal spectra show that only in the case of amplitude modulation the DFT spectrum of the modulated bounded signal can be similar to the original signal spectrum, although there occur random deviations. On the other hand, if phase modulation is present, then the DFT spectrum of the modulated bounded signal not only shows random deviations but also amplitudes of peaks existing in the original spectrum are diminished, and consequently similarity to the original signal spectrum can be significantly blurred.

On Discrete Fourier Spectrum of Randomly Modulated Signals

Artificial Satellites

{"article-title":"On Discrete Fourier Spectrum of Randomly Modulated Signals"}

In this work the problem of characterization of Discrete Fourier Transform (DFT) spectrum of an original complex-valued signal modulated by random fluctuations...

On Discrete Fourier Spectrum of Randomly Modulated Signals

Published Online: Feb 10, 2011

Page range: 143 - 152

DOI: https://doi.org/10.2478/v10018-011-0003-5

Keywords
Discrete Fourier Transform, signal spectrum, amplitude modulation, phase modulation, random fluctuations

This content is open access.

On Discrete Fourier Spectrum of Randomly Modulated Signals

Published Online: Feb 10, 2011

Page range: 143 - 152

DOI: https://doi.org/10.2478/v10018-011-0003-5

KeywordsDiscrete Fourier Transform, signal spectrum, amplitude modulation, phase modulation, random fluctuations

This content is open access.

Keywords
Discrete Fourier Transform, signal spectrum, amplitude modulation, phase modulation, random fluctuations