  The power spectra of the fluctuation noise of the solar active region (AR)
areas and magnetic fluxes sequentially observed in time contain information
about their geometrical features and the related fundamental physical
processes. These spectra are analysed for five different ARs with various
magnetic field structures. The goal of this work is to detect the
characteristic properties of the Fourier and wavelet spectra evaluated for the
time series of the fluctuating areas and radial magnetic fluxes of the active
regions. Accordingly, this work gathers information on the properties of noise
in the different cases considered. The AR area and radial magnetic flux time
series were built using SHARP magnetogram datasets that cover nearly the entire
time of the ARs' transits over the solar disk. Then we applied Fourier and
wavelet analyses to these time series using apodization and detrendization
methods for the cross-comparison of the results. These methods allow for the
detection and removal of the artefact data edge effects. Finally, we used a
linear least-squares fitting method for the obtained spectra on a logarithmic
scale to evaluate the power-law slopes of the fluctuation spectral power versus
frequency (if any). According to our results, the fluctuation spectra of the
areas and radial magnetic fluxes of the considered ARs differ from each other
to a certain extent, both in terms of the values of the spectral power-law
exponents and their frequency bands. The characteristic properties of the
fluctuation spectra for the compact, dispersed, and mixed-type ARs exhibit
noticeable discrepancies amongst each other. It is plausible to conclude that
this difference might be related to distinct physical mechanisms responsible
for the vibrations of the AR areas and/or radial magnetic fluxes.
