Thomas Damaseaux 
  
TOPOGRAPHIC MAP GENERATION IN 
HIGH MOUNTAINOUS AREAS BY MEANS OF InSAR DATA 
Thomas Damoiseaux 
Aero-Sensing Radarsysteme GmbH 
c/o DLR Oberpfaffenhofen 
82234 Welling, Germany 
Phone/Fax: +49-8153-281542/-281543 
Email: thomas.damoiseaux @dlr.de 
Technische Universitit Dresden 
Fakultät Forst- Geo- und Hydrowissenschaften 
Institut für Kartographie 
Abstract 
This paper examines to what extent a new approach to the production of maps can be taken using radar remote 
sensing in the cartography of mountainous areas. This will be analyzed with a test area of the Bavarian Alps, 
Germany. The basis are high resolution, In-SAR data from the airborne AES-1 sensor. After data preparation 
the information is extracted from the multi-frequency and multi-temporal data with the aim of making 
topographic maps. These products are then compared with requirements for the high-mountain cartography, 
and the contribution that radar remote sensing can make to the high-mountain cartography is assessed. 
1. Introduction 
The goal of a topographic map is that it reflects the nature of the landscape with its characteristic 
geomorphological elements. These elements should be illustrated in a map as true to form and as vividly as 
possible. In general data from aerial photography systems and optical remote sensing as well as from terrestrial 
topographic ground surveys serve as a basis for map production. 
This paper analyzes to what extent and with which methods radar remote sensing is able to achieve that aim of 
a topographic map. The imaging of the ground surface by means of radar systems with synthetic aperture 
(SAR) generates first a two-dimensional map of the illuminated area. In addition, with the help of the methods 
of SAR interferometry (InSAR), the ground surface can be reproduced in three dimensions. The SAR images, 
the coherence image and the digital elevation model (DEM) now serve as a basis for extracting information 
from the radar data. From this information a model of the real world is generated which then describes reality 
as well as possible so that cartographic products can be derived from it. 
To achieve this goal the methods of digital image processing and pattern recognition are used. One can 
describe the land cover of the given area and the altitude information in form of contour lines. Land cover and 
contour lines are then examined with the help of a ground-truth data set to control their accuracy. In a further 
step they are measured against topographic mapping criteria for high mountains. Finally a statement can be 
made in regard to the quality of the maps rendered from InSAR data on various scales. 
The paper is structured as follows: Chapter 2 treats the InSAR principles, while chapter 3 outlines the 
processing chain of making topographic maps. In chapter 4 an overview of the AES-1 sensor is given and 
chapter 5 handles the theory of information extraction. Chapter 6 deals with the application to a concrete area 
and discusses the results. In the conclusion a view to the future of the project is given. 
2. InSAR Principles 
Active microwave systems work in the frequency range of 0.3 to 300 Ghz [Ulaby et al, 1981], which 
corresponds to a wavelength range of 1 m to 1 mm. In this frequency range clouds and rain can be penetrated 
almost without any hindrance. As the high-frequency pulses are emitted by the sensor itself, the system works 
with its own illumination and is independent of daylight. 
  
54 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part Bl. Amsterdam 2000. 
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