In this study,Differential Interferometric Synthetic Aperture Radar Interferometry(DInSAR)of artificial Corner Reflectors(CRs)were validated in the area of fast and nonlinear deformation gradient caused by active coal...In this study,Differential Interferometric Synthetic Aperture Radar Interferometry(DInSAR)of artificial Corner Reflectors(CRs)were validated in the area of fast and nonlinear deformation gradient caused by active coal longwall exploitation.Three Sentinel-1 datasets were processed using conventional DInSAR,Persistent Scatterer Interferometry(PSI),and Small BAseline Subset methods implemented in ENVI SARscape™.For evaluation,leveling and Global Navigation Satellite System(GNSS)measurements were used.Considering the challenge of snow cover,the removal of all winter images was not a successful strategy due to the long temporal baseline and strong movement,which cause phase unwrapping problems and underestimate the real deformation.The results indicate that only conventional DInSAR and SBAS with low network redundancy allow us to capture maximal deformation gradient and the root mean square error calculated between the CRs and the ground truth is on the level of 2–3 cm for the vertical and easting deformation component,respectively.For the small deformation gradient represented by the permanent GNSS station(4 cm/year),all SBAS techniques appeared to be more accurate than DInSAR,which corresponds to higher redundancy and better removal of the atmospheric signal.In contrast,DInSAR results allowed to capture information about two subsidence basins,which was not possible with SBAS and PSI approaches.展开更多
Multi-baseline synthetic aperture radar interferometry(InSAR),capable of mapping 3D surface model with high precision,is able to overcome the ill-posed problem in the single-baseline InSAR.Current tandem SAR mission u...Multi-baseline synthetic aperture radar interferometry(InSAR),capable of mapping 3D surface model with high precision,is able to overcome the ill-posed problem in the single-baseline InSAR.Current tandem SAR mission utilizes a two-stage global coverage to get the dual-baseline interferograms,which achieves the trade-off between the unwrapping errors and height precision.However,the baseline adjustment will decrease the timeliness of the data acquisition,which is not suitable for monitoring temporal changes of the ground targets.Designing a SAR mission with the single-pass multi-baseline acquisition will improve the practical capability in fast 3D reconstruction.Following the asymptotic 3D phase unwrapping proposed for the airborne array InSAR system,it is possible to get a reliable 3D reconstruction using very sparse acquisitions but the interferograms should follow the optimal baseline configuration.In this article,a new concept of tandem multi-antenna SAR interferometry system for acquiring optimal single-pass multi-baseline interferograms is proposed.Two indicators,i.e.,expected relative height precision and successful phase unwrapping rate,are selected to optimize the system parameters.Additionally,taking the satellites with two antennas as an example,the performances of various baseline configurations in typical scenarios and the impact of different error sources are investigated correspondingly.The simulation-based experiments demonstrate that the proposed system acquires the optimal MB interferograms for asymptotic 3D phase unwrapping,and thus enables good performance in both urban and forest area in a single flight.This system has the potential applications in accurate digital surface model acquisition,3D target recognition,and biomass estimation.展开更多
基金The research infrastructure that has been used for computation purposes was created within the project EPOS-PL(POIR.04.02.00-14-A003/16)EPOS-PL+(POIR.04.02.00-00-C005/19-00)European Plate Observing System,funded by the Operational Programme Smart Growth 2014-2020,Priority IV:Increasing the research potential,Action 4.2:Development of modern research infrastructure of the science sector and co-financed by the European Regional Development Fund.
文摘In this study,Differential Interferometric Synthetic Aperture Radar Interferometry(DInSAR)of artificial Corner Reflectors(CRs)were validated in the area of fast and nonlinear deformation gradient caused by active coal longwall exploitation.Three Sentinel-1 datasets were processed using conventional DInSAR,Persistent Scatterer Interferometry(PSI),and Small BAseline Subset methods implemented in ENVI SARscape™.For evaluation,leveling and Global Navigation Satellite System(GNSS)measurements were used.Considering the challenge of snow cover,the removal of all winter images was not a successful strategy due to the long temporal baseline and strong movement,which cause phase unwrapping problems and underestimate the real deformation.The results indicate that only conventional DInSAR and SBAS with low network redundancy allow us to capture maximal deformation gradient and the root mean square error calculated between the CRs and the ground truth is on the level of 2–3 cm for the vertical and easting deformation component,respectively.For the small deformation gradient represented by the permanent GNSS station(4 cm/year),all SBAS techniques appeared to be more accurate than DInSAR,which corresponds to higher redundancy and better removal of the atmospheric signal.In contrast,DInSAR results allowed to capture information about two subsidence basins,which was not possible with SBAS and PSI approaches.
基金supported in part by the National Nature Science Foundation of China under grants 61991422 and 62201158.
文摘Multi-baseline synthetic aperture radar interferometry(InSAR),capable of mapping 3D surface model with high precision,is able to overcome the ill-posed problem in the single-baseline InSAR.Current tandem SAR mission utilizes a two-stage global coverage to get the dual-baseline interferograms,which achieves the trade-off between the unwrapping errors and height precision.However,the baseline adjustment will decrease the timeliness of the data acquisition,which is not suitable for monitoring temporal changes of the ground targets.Designing a SAR mission with the single-pass multi-baseline acquisition will improve the practical capability in fast 3D reconstruction.Following the asymptotic 3D phase unwrapping proposed for the airborne array InSAR system,it is possible to get a reliable 3D reconstruction using very sparse acquisitions but the interferograms should follow the optimal baseline configuration.In this article,a new concept of tandem multi-antenna SAR interferometry system for acquiring optimal single-pass multi-baseline interferograms is proposed.Two indicators,i.e.,expected relative height precision and successful phase unwrapping rate,are selected to optimize the system parameters.Additionally,taking the satellites with two antennas as an example,the performances of various baseline configurations in typical scenarios and the impact of different error sources are investigated correspondingly.The simulation-based experiments demonstrate that the proposed system acquires the optimal MB interferograms for asymptotic 3D phase unwrapping,and thus enables good performance in both urban and forest area in a single flight.This system has the potential applications in accurate digital surface model acquisition,3D target recognition,and biomass estimation.
