300
DEM pixel spacing
90 m*90 m
DEM data size
2000x2000
Orbit ERS-1/2
24221/04548
Date acquired ERS-1/2
1996-3-2/3
wavelength
5.6cm
azimuthxrange pixel spacing
4.040m x 7.904m
time of first state vector
73128.364 s
azimuth line time
6.0244484e-004 s
semi-major axe of the Earth
6378137.0000 m
semi-minor axe of the Earth
6356752.3141 m
Table 1: Simulation parameter
Fig. 3 the external DEM
Flattened Synthetic Interferogram
500 1000 1500 2000
range pixels
Fig. 5 the external DEM
Fig. 4 represents the unflattened interferogram. One thing
should be noticed that the interferogram is very dense. Fig. 5
represents the flattened interferogram and its fringes compared
to the Fig. 4 become sparse. We know the height ambiguity is
about 150m by calculating the parameters of ERS-1/2. So the
simulated interfergram should have about 3 fringe changes.
Meanwhile from the trend of topographical changes of Fig. 4
we can see the trend of the simulated interferogram match the
external DEM very well. The result shows a good agreement
between simulation and the theory.
4. CONCLUSIONS
An new interferogram simulator has been developed with real
orbit parameters, real radar sensor parameters and geometry
model. The test experiment shows that the simulator is reliable
for the following reasons: the interferogram phase changes
corresponds to the topographical changes and the trend of the
simulated interferogram matches the external DEM very well. It
is a good assistant tool not only for validaition of phase-to-
height converion and geocoding processing, but also for D-
InSAR processing. Future work is to pay more attention to
improve the efficiency of our algorithm and further study the
application of our simulation method.
REFERENCES
Zhong Lu, 2007, “InSAR Imaging of Volcanic Deformation
over Cloud-prone Areas-Aleutian Islands,”
PHOTOGRAMMETRIC ENGINEERING & REMOTE
SENSING, vol.73, No.3, pp.245-257
R. F. Hanssen, T. M.Weckwerth, H. A. Zebker, and R. Klees,
1999 “High-resolution water vapor mapping from
interferometric radar measurements,’’Science, vol. 283, pp.
1295-1297.
Fig. 4 the external DEM
Curlander J. C., 1982, “Location of Spacebome SAR Imagery”,
IEEE Trans, on Geoscience and Remote Sensing, Vol. GE-20,
No.3, pp.359-364. SAR Toolbox algorithm specification,
Earthnet online, ESA