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etric height 
lion phase 
> has been 
1er without 
EM. 
by bilinear 
ms and the 
s improved 
ence of 5m 
"he Wiener 
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ution of the 
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s important 
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AR height 
asurements, 
  
Marc Honikel 
  
while restoring them in case of degradation. In order to avoid the introduction of corrupted measurements in the fusion 
process, an attribute has been derived, indicating the expected error of the measurement. 
This local approach leads to a global improvement of the resulting height measurements with respect to 
e Amount of valid measurements (reduction of measurement holes) 
o DEM error distribution 
- Reduction of mean and root mean square error 
- Extreme reduction of outliers. 
The achieved results are much superior compared to the initial results from the single sensor data sources and encourage 
the work on a complete numerical realization of the Wiener phase estimation in the spatial domain. 
  
Figure 10. Restored interferogram draped over the Wiener improved elevation model 
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Honikel, M., 1998. Fusion of Optical and Radar Digital Elevation Models in the Spatial Frequency Domain, Proc. 2" 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part Bl. Amsterdam 2000. 155