Geopositioning Capability of Highresolution Satellite Stereo Imagery for Highrise Buildings in Urban Area

Abstract:

This paper focuses on the geopositioning capability and accuracy evaluation of highresolution satellite stereo imagery for highrise buildings in urban area.The experimental result shows that ground control points (GCPs) are needed in order to improve the geopositioning accuracy derived from the rational function model (RFM).The traditional geometric correction model in object space is effective when GCPs and independent check points (ICPs) are both on flat ground,but the computation error caused by elevation extrapolation appears when ICPs are on high building rooftops.A modified geometric correction model in object space is then proposed to eliminate the error introduced by huge elevation difference on high buildings.The result shows that a geopositioning accuracy of 0.6m in horizontal direction and 0.8m in vertical direction was achieved in Shanghai central district with high buildings involved,proving the effectiveness of this modified model.

Key words:satellite stereo imagery; highresolution; rational function model; geometric correction model; geopositioning accuracy