6. CONCLUSION 
and Remote Sensing, 54 (2-3), pp. 130-137. 
THE 
22 
New applications can be developed by using the power of mod 
em GPUs for SAR simulation purposes. Interactive applications 
need real-time simulators. Especially applications in education, 
mission planning and interactive image analysis depend on real 
time simulation results. Nowadays, this is possible even using 
low-cost hardware and software solutions. 
The real-time simulator SARViz simulates a wide variety of dif 
ferent SAR configurations. Using the programmable shaders of 
modem GPUs, SAR images can be visualized as fast as scenes 
in modem computer games. As well as computer graphics visu 
alizations get more and more complex and realistic, the SAR si 
mulation can benefit from these developments by simulating 
more and more complex scenes faster and faster. Although the 
real-time simulation is not providing as realistic results as other 
SAR simulators, for a variety of applications the results are suit 
able. 
High-resolution data fusion between optical and radar images 
must consider the terrain and the shape of objects of interest. 
Change detection based on the fusion of different data sets can 
be assisted by simulations. Mainly due to erroneous and incom 
plete 3D models, simulation assisted automatic change detection 
approaches suffer from high false-alarm rates. More reliable 
results can be expected using interactive change detection meth 
ods. SARViz can provide real-time SAR simulation of 3D mod 
els as well as optical visualizations of these models. Due to the 
possibility of combining different data sets, SARViz is a fast 
and reliable tool for image interpretation. 
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The Rt 
KEY WORD 
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