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Title
International cooperation and technology transfer
Author
Mussio, Luigi

8
measurements, performed in static mode with a
sampling time of 15 sec in continuous acquisition for
two days, double frequency receivers were used.
Data processing has been performed by means of
BERNESE vers.4.0 scientific software. In fig.4 are
shown the rms values at 1c level of the WGS84
geographic coordinates of 25 vertices of the network.
During 1998, about 80 photographic support points
have been measured, by means of the GPS technique,
for a digital photogrammetry application along the NE
rim of the phlegrean caldera (Camaldoli hill). Also if a
future use of these points for monitoring purposes is not
planned, as they will not be remeasured, the
coordinates set thus calculated could be utilized,
besides the generation of DTM (Digital Terrain Models)
in aerophotogrammetric applications, also for SAR
Interferometric applications (phase unwrapping).
Fig.4 RMS values of the WGS84 geographic
coordinates of the Phlegrean Fields network at 1c level
2.4 Sar Interferometry (INSAR)
Both the classical topographic techniques and the GPS
technique, also if they are able to allow a tridimensional
positioning of one point with up to under centimeter
precisions, suffer from the disadvantage of providing
informations related to a discrete number of points; so,
in this case, is useful to utilize, together with these
techniques, others which are able to allow an areal
estimation of the deformation field.
The INSAR is well suited for this purpose, providing
also a ground deformations control during the time by
means of the application of the technique in differential
mode (DINSAR).
Besides, the results obtained by spirit leveling and GPS
measurements could both be used for a validation of
those ones obtained by means of INSAR, and for a
support in the interferometric SAR data processing
(phase unwrapping): the innovative aspects of this
research project are therefore directed to an integration
of INSAR data with data obtained by means of other
topographic techniques, classical or satellite
techniques.
The area selected for satellite (ERS1/2) INSAR data
processing is a rectangle of about 40x30 km centred on
the Phlegrean Fields. The images have been processed
by means of PCI software on UNIX platform.
In this initial phase it has been decided to generate two
interferograms (with a pixel dimension of 40x40 m), the
first one with August 1995/August 1996 images (fig.5)
and the second one with November 1995/February
1997 images.
The possibility to get, for the first interferogram, a
baseline short enough (about 11 m), has allowed to
avoid the application of the interferometric technique in
differential mode. In this case, the phase contribution of
the topography to the interferometric signal, can be
considered negligible, thus the resulting information of
fig.5 can be evaluated only as a deformation signal.
Fig.5 August 1995/August 1996 Interferogram of the Phlegrean Fields: in the figure it is possible to note just more then
one fringe
From the an
deformation,
centred in P
at the east s
Towards th
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Naples.
Thus, in fi<
deformation
band=5.6 cr
value deduc
be lightly co
dimension.
The second
demonstrate
leveling nr
deformation:
of 1996; tf
obtained on
interval shoi
The strong
coherence n
a larger bt
necessity 1
contribution
to obtain sue
3. SURVE'
3.1 High pr«
The spirit le>
formed by 2
m, on about
The last sp
network (M
autolevels
micrometers
Fig.6 Gee