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compensation data, and the corner reflector ground control points. Radiometric processing, mosaicking and filtering 
of the orthorectified SAR image are final postprocessing steps. All processing software used in the projects 
mentioned (excluding the GPS and INS processing software) is running in Linux environment and was developed by 
Aero-Sensing. Further informations on SAR processing are given in (Wimmer et al., 2000). 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
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Radar AeS-1 + m SAR Processing pepe! Archiving 
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Figure 3: Block diagram of the AeS-1 system Figure 4: SAR ortho image, Indonesia, spatial 
resolution 2.5 m x 2.5 m 
3. MAPPING PROJECTS IN INDONESIA, BRAZIL, AND VENEZUELA 
3.1 Indonesia 
The mapping project in Indonesia took place from July 1997 to January 1998. 46,000 km? on Java island, on the 
Molucca islands and on Irian Jaya were mapped with a geometric image resolution of 2.5 m x 2.5 m and a height 
accuracy of 2 m. The goal of this project was to provide geoinformation data for remote tropical areas on the 
Moluccas islands and in Irian Jaya, which were mapped unsufficiently and just in small scale maps before. 
Additionally, in all mapped areas existing topographic maps were updated and completed with thematic forest 
information, derived by visual interpretation. Because of this, the image resolution was more important than the 
height accuracy, but the image resolution takes notice of the vast mapping areas: Often, a compromise must be 
fulfilled between application, image resolution, height accuracy, the dimensions of the project area and of course, 
the costs of a project. Nevertheless, different forest classes and other land use classes could be determined and 
mapped. Figure 4 shows a SAR ortho image, captured within the mapping project in Indonesia. As in many other 
countries, it wasn't allowed to process the collected data outside the country. In this way, the complete SAR 
processing chain had to be set up in Indonesia, run by indonesian staff. The project in Indonesia was extended later 
with additional areas on Irian Jaya and the Molucca islands. 
3.2 Brazil 
In Brazil, an area of about 10,000 km? in the Northeastern part of the country was mapped in October 1998 with a 
maximum geometric resolution of 0.5 m x 0.5 m and a height accuracy of 0.25 m. The purpose of this project was to 
provide irrigation for drought areas using water from the large, nearby river Rio Sáo Francisco. High accurate 
interferometric DEM's were used to plan water pipes, laid optimally, taking advantage of ground slope and natural 
water run offs. Because of the swath width of about 2 km and the desired height and position accuracies, the flight 
altitude was about 3,000 m. Figure 5 shows a part of a shaded DEM. The whole processing chain was installed in 
Brazil and run by brazilian staff. Usually, the amount of ground activities increases with the desired accuracies, thus, 
a lot of corner reflector and transmitting point locations had to be measured using differential GPS. Finally, the data 
acquisition in this project could be finished according to a high data collection rate in just two weeks, by meeting all 
data quality requirements. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part Bl. Amsterdam 2000. 21