Entity

Time filter

Source Type


Jiang Y.-H.,Hubei Engineering University | Zhang G.,Hubei Engineering University | Zhang G.,Satellite of Surveying and Mapping Application Center
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2011

The inner calibration technology of spaceborne SAR, as an effective way of eliminating the error deduced from inaccurate SAR positioning parameters to improve positioning accuracy, has been studied worldwide. Based on the imaging characteristics of spaceborne SAR and its rigorous sensor model, this paper constructs the rigorous geometric model for SAR inner calibration, and then proposes the inner calibrating algorithm. CRS1 images over Inner Mongol are used as test data. The positioning accuracy of the model is improved a lot after inner calibration which verifies the feasibility and accuracy of the algorithm. © 2011 IEEE.


Pan H.,Hubei Engineering University | Zhang G.,Hubei Engineering University | Zhang G.,Satellite of Surveying and Mapping Application Center | Chen T.,Hubei Engineering University
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2011

This paper presents a general method to generate the linear push-broom cameras and SAR epipolar images, which is based on RPC model and image-space adjustment model for relative orientation. The epipolar curves are derived by endpoints growing and fitted with straight lines and hyperbolas. And the RPC model is used to replace the epipolar geometry model and the sensor model of original images. Ikonos along-track stereo, TerraSAR-X same side-looking stereo and the mixture stereo of TerraSAR-X SLC image and SPOT 5 THX are tested to evaluate this method. The remaining vertical parallax of the Ikonos, TerraSAR-X and mixture stereos is 0.0040 pixels, 0.0041pixel and 0.56 pixels, respectively. © 2011 IEEE.


Xiaotian S.,Hubei Engineering University | Guo Z.,Hubei Engineering University | Guo Z.,Satellite of Surveying and Mapping Application Center | Xia W.,Satellite of Surveying and Mapping Application Center
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012

Generally, there are two ways to generate Digital Elevation Model (DEM) using synthetic aperture radar (SAR) data, which are Interferometer Synthetic Aperture Radar(InSAR) and radargrammetry. Considering the disadvantages of InSAR data, such as the limit of terrain and the influence of water content, the application field of InSAR is relatively limited, while radargrammetry is more widely applied since it does not have such limits. However, for high-precision stereo SAR imagery, since the terrain distortion caused by shooting an gle cannot be eliminated and the speckle noises are obvious, the classical matching algorithms for optical stereo images do not have the same effect on SAR data. Based on the experience of optical stereo image matching, this paper proposes a new algorithm which combines the feature of SIFT image matching, region-based least squares matching and TIN. First, SIFT matching is used as the initial matching to obtain the sparse DEM, then by using TIN the matching points are forecast, finally the region-based least squares matching is adopted to get accurate matching points. In this paper, COSMO-SkyMed and TSX stereo images of Lanzhou area are used to validate the proposed method. Experiment results show that the algorithm can be effectively used in stereo SAR matching and high-precision DEM production.


Fei W.-B.,Wuhan University | Zhang G.,Wuhan University | Zhang G.,Satellite of Surveying and Mapping Application Center | Li Z.,Wuhan University
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2011

InSAR is a technique to extract three-dimensional information on the terrain topography from the phase of the SAR signal and the rational polynomial coefficient (RPC) model has raised considerable interest in the photogrammetry and remote sensing communities. Some work has been done on the RPC model's substitutability for the SAR rigorous sensor model, which is based on the Range-Doppler (RD) equation, moreover, there have been study discussing the substitutability of the RPC model to InSAR (Interferometric SAR) rigorous geometrical sensor model, which is based on the RD equation and phase equation. For the InSAR process, baseline evaluation is very important for the final extracted DEM, but when using RPC model for the replacement of InSAR rigorous geometrical sensor model, the parameter of baseline cannot be included explicitly. Hence, we contend that phase evaluation can be substituted for the baseline evaluation, and it can be applied for RPC model, which can compensate the error caused by orbit and can rebuild the real phase. © 2011 IEEE.


Zhang G.,Wuhan University | Zhang G.,Satellite of Surveying and Mapping Application Center | Li Y.,Wuhan University | Li Z.,Wuhan University
Science China Technological Sciences | Year: 2010

Object-based change detection has been the hotspot in remote sensing image processing. A new approach toward object-based change detection is proposed. The two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding objects. Then change detection is implemented based on the integration of corresponding objects' intensity and texture differences. Experiments are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and noise. Supplementary color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral images. Some verification work is carried out to show the accuracy of the proposed approach. © Science China Press and Springer-Verlag 2010.

Discover hidden collaborations