Deformation Sequence Acquisition And Prediction Modeling Of Beijing Urban Area Based On D-TomoSAR Technology

In recent years,with the increasing availability of high-resolution SAR data resources,there has been an increasing need to acquire target 3D(distance-azimuth-height)information in many application scenarios.In research fields such as urban infrastructure dynamic deformation monitoring,important project safety monitoring,environmental monitoring,and geological disaster monitoring,in addition to obtaining three-dimensional information about the target,it often requires fourth-dimensional information,which means that the change of target height in time dimension,that is,deformation information.The emergence of tomographic SAR technology meets the needs of three-dimensional information applications.Based on the traditional two-dimensional SAR(azimuth-distance)imaging plane,multiple SAR complex images of the same area are used to synthesize apertures at the elevation to obtain the target's three-dimensional information.When multiple SAR images are acquired in a long time series,the Tomographic SAR can be considered as the synthetic aperture in the time dimension,so as to obtain the deformation rate information of the target along the height direction,and realize the four-dimensional imaging.With the batch acquisition of multi-platform SAR data and the unique three-dimensional and four-dimensional high-resolution imaging capabilities of tomographic SAR technology itself,this information acquisition method has attracted extensive attention and in-depth research from scholars at home and abroad.It has important application prospects in many fields such as geology,ecology and geography.Differential TomoSAR technology has its unique technical advantages in the field of urban deformation monitoring.It can obtain high-precision(mm-level)deformation variables in key areas and large data coverage.And the three-dimensional structure and deformation information are acquired at the same time,the acquired data sequence is dense.But at the same time,the Differential TomoSAR technology also faces some difficult problems,mainly the application of high-precision imaging algorithms and the lack of effective prediction methods for the time-series deformation data obtained,and it cannot provide predictive analysis of the long-term deformation of the monitoring target.Based on this idea,this article introduces the basic principle and data processing process of Differential TomoSAR imaging technology.It uses TerraSAR image data in Beijing area for practical application,and obtains three-dimensional structure and surface deformation information in the experimental area.Combined with the deformation prediction model to establish a deformation prediction evaluation mechanism based on the deformation information.This has practical significance for realizing timely and effective deformation analysis of buildings in key areas.