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In the conventional MST radar echo signals analysis methods,
FFT and correlation functions, assume the turbulence wind
field to be stationary. Although the STFT ( short time Fourier
trans- form ) provided some help to get more about the time
dependent information, the window selection unfortunately
affects the re- sult. The multi-resolution of wavelets
transform provides a new way, to interpret the radar signals
with different time and frequency scales, to get more
information of MST observation of atmospheric dynamics .
Analyzing the Doppler velocity, the time dependent turbulent
fluctuation can be clearly identified by the wavelets
transform. And it also provides us the dynamical procedure of
turbulent. In this report, we show that the irregularity of the
atmosphere is intermittent with time in the radar volume , we
also find that: (1)Wavelets transform is compared well with the
conventional analyzing methods in the MST radar atmosphere
observations. (2)The Wavelets transform provides us an
analyzing basis to the MST radar signals without the assumption
of stationality and with the property of statistic. (3)The
phase of the Wavelet transform provides us a new way to follow
the temporal variation of the amplitude of different Doppler
frequencies. Since the intermittence of the atmosphere back
scattering is decomposition, the temporal turbulent mechanism
is hopeful to be solved. And this leads to the question of the
"universal spectrum" if is meaningful with the assumption of
homogenous and stationary by Kolmogrove. In the future, the
mechanism causing these variations may be identified more
easily by this technique. And the ability of mullet-resolution
the wavelet an- alysis may lead us to the fractal structure of
the atmosphere.
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