Research On The Application Of InSAR Technology In Flood Control Deformation Monitoring

Jiangxi province is located in the south bank of the middle and lower reaches of the Yangtze River.Unique topography and climate conditions,rich thick water resources condition,provides an important support for the economic development of jiangsu province,but also because of precipitation in space-time distribution and interannual change is big,year distribution is uneven,makes the jiangxi flood drought disasters frequently,may cause catastrophic accidents,cause unnecessary casualties and economic loss and the destruction of the natural environment.Traditional ground monitoring method can only obtain deformation data in a small range,but cannot obtain deformation data in a continuous large range.The differential interferometry of SYNTHETIC aperture radar(SAR)can monitor large area and small ground deformation in multiple periods of time with high precision.It satisfies the advantages of wide measuring range,high precision,controllable cost,free from climate influence,and 24-hour monitoring.It can also detect the unreachable areas,making up for the shortcomings of traditional monitoring methods.Due to its obvious advantages in surface deformation monitoring and its development potential in the future,radar dry differential interferometry has been widely used.In this paper,PS-InSAR technology is used to process time series InSAR data by using THE SAR image transfer registration method,the PS selection method of adaptive threshold segmentation constraint and the spatio-temporal dimension phase unwrapping method.Through data processing,combined with the collected data,the deformation of flood control facilities in Qiushui Square and surrounding areas in Nanchang city was monitored,and the deformation information in the area was analyzed comprehensively,which can provide decision support for water conservancy project safety monitoring and disaster early warning.The main research contents and results are as follows:(1)The basic principle and process of InSAR terrain extraction and InSAR technology are systematically introduced and analyzed.(2)The data processing flow of InSAR technology is described in detail,and key technologies such as highly coherent target selection,phase unwrapping,baseline correction,model establishment and solution are analyzed.(3)Taking the Ganjiang River basin in Nanchang as the research object,the application research of PS-InSAR technology in water conservancy safety monitoring was carried out by using cosmo-Sky Med data.The application results show that the InSAR interferometry technology can monitor the large area of small ground deformation with high precision,so as to achieve the geometric measurement of millimeter level of surface deformation.Compared with the traditional GPS and leveling based on the discrete point deformation monitoring technology,InSAR technology has the unique advantages of high precision,wide monitoring range,monitoring continuity,little weather influence,convenient monitoring implementation,relatively low cost and high safety.