The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008
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pixel with view angel and relative position changing of the
scatterers. The main characteristics of multi-image processing
method are that it utilizes a single master stack of differential
interferograms and that only time-coherent pixel. According to
the description of the PS technique which base on Colesanti et
al., Ferretti et al., the key processing steps of the PS technique
are the following (1 Computation of the interferograms, (2)
Computation of the differential interferograms using a digital
elevation model, (3) Preliminary estimation of the presumably
most coherent pixel, (4) Refinement of third step; the coarse
grid of PS candidates estimate the long wavelength part of the
atmospheric signal. After interpolation of these estimates, the
differential interferograms are corrected, and additional PSs are
computed [Ferretti et al, 1999, 2004; Hooper, 2006].
3. AERIAL PHOTOGRAMMETRY
Traditionally, Photogrammetry has defined as the process of
deriving metric information about an object through
measurements made on photographs of the object. Aerial
photogrammetry is the taking of photo from the air with a
camera mounted on an aircraft, helicopter, and similar vehicle.
Aerial photogrammetry is used in land-use planning, archeology,
environmental and surface monitoring and other fields [Jensen
2007]. In aerial photogrammetry, the reference coordinate
system, or datum is defined by the Ground Control Points
(GCPs) [Mikhail et al, 2001]. In this research, coordinate
systems were defined to UTM-56 and WGS84. GCPs are
surveyed by Leica GPS-500 system. Each GCP was measured
using static method and operating time was over 30min. 6 GCPs
were used. GCPs coordinate are table 1.
ID
Latitude
Longitude
Hight
181 cp1
-33.89042579
151.2336121
90.48899
181cp2
-33.88435260
151.2489353
56.73410
181cp3
-33.90650849
151.2317450
54.84594
181cp4
-33.90785047
151.2474110
91.80488
181cp5
-33.91723083
151.2264035
51.00231
181cp6
-33.91877307
151.2459852
55.55110
Table 1. Coordinates of Ground Control Points
Figure 1. GCP Surveying using GPS
4. EXPERIMENT
The test field is residence area at Sydney in the New South
Wales, Australia. In the PSInSAR process, test field is covered
all Sydney area (15x15km). In the aerial photogrammetry that
to get detail information, test field is minimized small confined
region ( 1.5 x lkm).
Figure 2. GCP Surveying using GPS
Figure 3. Aerial photo processing using SOCETSET
Figure 4. Test Field in Sydney (Google Earth)
This research used European Remote Sensing 1 and 2 (ERS-
1/2) radar images (C-band) using PSInSAR and Aerial photo
using Photogrammetry to investigate the ground deformation at
Sydney in the state of New South Wales, Australia. The 18
images of ERS-1/2 (04/1992-04/1997) were found in the search
for the available images over the Sydney area. The Persistent
Scatterer candidate identification process was progressed to
identity all the stable natural reflectors according to the