Helsinki University of Technology
Department of Surveying
The aim of this study was to find out the possibilities to produce digital elevation models from radar satellite imagery. At the same time the goal was to improve the DEM production processes in Novosat Ltd.
There are two techniques used for DEM production from radar satellite imagery. In radar interferometry the height difference and direction is calculated from phase differences of two radar images. This technique provides very accurate results, but it sets high limitations upon the imagery used.
In radar stereoscopy the height definition is based on the geometric differences of two radar images. The difference of target location is measured on image plane. These parallaxes give the amount and the direction of height difference. The radar stereoscopy gives slightly rougher results than interferometry, but it does not set so high limits for the data itself.
In Novosat Ltd, DEMs are primarily made by radar interferometry. If there is no good enough data available or the quality of data can not be defined beforehand the only solution is to produce the digital elevation model by means of radar stereoscopy.
Keywords: radar, digital elevation model (DEM), radargrammetry, radar stereoscopy, radar interferometry
Language: Finnish, English abstract