Up to now, only space-borne sensors have been used for differential interferometry. This implies ... more Up to now, only space-borne sensors have been used for differential interferometry. This implies several problems: Space-borne SAR data is affected by atmospheric effects, often causing great unreliability of differential interferograms. Also the loss of coherence over the long data acquisition intervals of space-borne sensors is critical. In the last time, the availability of suitable space-borne data has become a problem, too. Finally, for the very important field of catastrophe management, space-borne sensors are not flexible enough to be really helpful. Airborne sensors overcome the problems mentioned above, but require new approaches for data processing and error correction. Based on data acquired by DLR’s experimental SAR system (E-SAR) in the interferometric repeatpass mode, we address in this paper the realisation of airborne differential SAR interferometry. This includes particularly the correction of residual motion errors in heavily decorrelated interferograms as well as ...
Proceedings. 2005 IEEE International Geoscience and Remote Sensing Symposium, 2005. IGARSS '05., 2005
The measurement of river currents can essentially contribute to determine river run-offs, whose k... more The measurement of river currents can essentially contribute to determine river run-offs, whose knowledge is of great importance, e.g. in climate research. Remote sensing would be a convenient way to regularly monitor river currents on a large scale. The paper presents results from an airborne flight campaign in which SAR techniques were used to map and estimate river surface currents. As the radar backscatter of rivers is usually very low due to the lack of a rough surface, the test sites must be chosen carefully. From a radar point of view the surface patterns behave like moving objects. These cause several effects in SAR images such as azimuth displacements that complicate measurements. It is shown that by taking them into account the estimation of river currents with SAR techniques is possible.
2009 IEEE International Geoscience and Remote Sensing Symposium, 2009
ABSTRACT In SAR tomography, the available information in the height direction is limited by the n... more ABSTRACT In SAR tomography, the available information in the height direction is limited by the number of different tracks that can be acquired in practice. To counterbalance this limitation, electromagnetic scattering models, properly exploiting the available a priori information, should be used, the ¿few¿ possible acquisitions should be accurately selected, and processing algorithms, guaranteeing the reliability of the results, should be employed. We present an approach for the reconstruction of the vertical reflectivity distribution of vegetated areas facing the above three points. In particular, an eigenvalue optimization procedure is exploited to design an ¿optimal¿ constellation to be flown, the peculiar features of ground and canopy are accounted for and an effective global optimization algorithm is used to enhance the reliability. The approach is tested with both simulated and real data acquired by the E-SAR system of DLR over the Dornstetten forest test-site.
IGARSS'97. 1997 IEEE International Geoscience and Remote Sensing Symposium Proceedings. Remote Sensing - A Scientific Vision for Sustainable Development, 1997
The paper is concerned about the application of motion compensation algorithms in interferometric... more The paper is concerned about the application of motion compensation algorithms in interferometric SAR data processing. An analysis of the effects of the error induced by the flat Earth assumption in motion compensating the data is included. Possible solutions to this problem via adjustments during and after the SAR processing and the geocoding are also discussed
2012 IEEE International Geoscience and Remote Sensing Symposium, 2012
ABSTRACT The paper reports about the first staring spotlight acquisitions with TerraSAR-X. It des... more ABSTRACT The paper reports about the first staring spotlight acquisitions with TerraSAR-X. It describes the commanding, the performance estimation and presents image results.
IGARSS'97. 1997 IEEE International Geoscience and Remote Sensing Symposium Proceedings. Remote Sensing - A Scientific Vision for Sustainable Development, 1997
Three DLR institutes, forming the cluster “Sensorik fuer Fernerkundung and Navigation”, and two i... more Three DLR institutes, forming the cluster “Sensorik fuer Fernerkundung and Navigation”, and two italian CNR institutes, I.R.E.C.E. and I.I.V., agreed on carrying out a joint airborne multisensor campaign in the Mt. Etna area in summer 1996. The site is of high geological interest. The deployment of an experimental SAR (E-SAR), a multispectral optical scanner (DAIS) and a wide angle stereo
Igarss '98 - 1998 International Geoscience and Remote Sensing Symposium, Proceedings Vols 1-5: Sensing and Managing the Environment, 1998
The paper presents a correction function which improves the phase accuracy in chirp scaling proce... more The paper presents a correction function which improves the phase accuracy in chirp scaling processing for squinted satellite borne SAR raw data with almost no increase of computational effort. The paper describes the phase errors introduced by chirp scaling processing. Simulations for a future L-band SAR system demonstrate the improvements caused by the correction function in the case of high
Up to now, only space-borne sensors have been used for differential interferometry. This implies ... more Up to now, only space-borne sensors have been used for differential interferometry. This implies several problems: Space-borne SAR data is affected by atmospheric effects, often causing great unreliability of differential interferograms. Also the loss of coherence over the long data acquisition intervals of space-borne sensors is critical. In the last time, the availability of suitable space-borne data has become a problem, too. Finally, for the very important field of catastrophe management, space-borne sensors are not flexible enough to be really helpful. Airborne sensors overcome the problems mentioned above, but require new approaches for data processing and error correction. Based on data acquired by DLR’s experimental SAR system (E-SAR) in the interferometric repeatpass mode, we address in this paper the realisation of airborne differential SAR interferometry. This includes particularly the correction of residual motion errors in heavily decorrelated interferograms as well as ...
Proceedings. 2005 IEEE International Geoscience and Remote Sensing Symposium, 2005. IGARSS '05., 2005
The measurement of river currents can essentially contribute to determine river run-offs, whose k... more The measurement of river currents can essentially contribute to determine river run-offs, whose knowledge is of great importance, e.g. in climate research. Remote sensing would be a convenient way to regularly monitor river currents on a large scale. The paper presents results from an airborne flight campaign in which SAR techniques were used to map and estimate river surface currents. As the radar backscatter of rivers is usually very low due to the lack of a rough surface, the test sites must be chosen carefully. From a radar point of view the surface patterns behave like moving objects. These cause several effects in SAR images such as azimuth displacements that complicate measurements. It is shown that by taking them into account the estimation of river currents with SAR techniques is possible.
2009 IEEE International Geoscience and Remote Sensing Symposium, 2009
ABSTRACT In SAR tomography, the available information in the height direction is limited by the n... more ABSTRACT In SAR tomography, the available information in the height direction is limited by the number of different tracks that can be acquired in practice. To counterbalance this limitation, electromagnetic scattering models, properly exploiting the available a priori information, should be used, the ¿few¿ possible acquisitions should be accurately selected, and processing algorithms, guaranteeing the reliability of the results, should be employed. We present an approach for the reconstruction of the vertical reflectivity distribution of vegetated areas facing the above three points. In particular, an eigenvalue optimization procedure is exploited to design an ¿optimal¿ constellation to be flown, the peculiar features of ground and canopy are accounted for and an effective global optimization algorithm is used to enhance the reliability. The approach is tested with both simulated and real data acquired by the E-SAR system of DLR over the Dornstetten forest test-site.
IGARSS'97. 1997 IEEE International Geoscience and Remote Sensing Symposium Proceedings. Remote Sensing - A Scientific Vision for Sustainable Development, 1997
The paper is concerned about the application of motion compensation algorithms in interferometric... more The paper is concerned about the application of motion compensation algorithms in interferometric SAR data processing. An analysis of the effects of the error induced by the flat Earth assumption in motion compensating the data is included. Possible solutions to this problem via adjustments during and after the SAR processing and the geocoding are also discussed
2012 IEEE International Geoscience and Remote Sensing Symposium, 2012
ABSTRACT The paper reports about the first staring spotlight acquisitions with TerraSAR-X. It des... more ABSTRACT The paper reports about the first staring spotlight acquisitions with TerraSAR-X. It describes the commanding, the performance estimation and presents image results.
IGARSS'97. 1997 IEEE International Geoscience and Remote Sensing Symposium Proceedings. Remote Sensing - A Scientific Vision for Sustainable Development, 1997
Three DLR institutes, forming the cluster “Sensorik fuer Fernerkundung and Navigation”, and two i... more Three DLR institutes, forming the cluster “Sensorik fuer Fernerkundung and Navigation”, and two italian CNR institutes, I.R.E.C.E. and I.I.V., agreed on carrying out a joint airborne multisensor campaign in the Mt. Etna area in summer 1996. The site is of high geological interest. The deployment of an experimental SAR (E-SAR), a multispectral optical scanner (DAIS) and a wide angle stereo
Igarss '98 - 1998 International Geoscience and Remote Sensing Symposium, Proceedings Vols 1-5: Sensing and Managing the Environment, 1998
The paper presents a correction function which improves the phase accuracy in chirp scaling proce... more The paper presents a correction function which improves the phase accuracy in chirp scaling processing for squinted satellite borne SAR raw data with almost no increase of computational effort. The paper describes the phase errors introduced by chirp scaling processing. Simulations for a future L-band SAR system demonstrate the improvements caused by the correction function in the case of high
Uploads
Papers