Integration of Cgps and Ground Meteorological Observations for Mitigating Atmospheric Effects on Insar
نویسندگان
چکیده
Repeat-pass interferometric synthetic aperture radar (InSAR) has been demonstrated useful for topographic mapping and surface deformation measurement. However, the interferometric phases of satellite radar signals are often seriously contaminated by atmospheric effects. Due to the highly variable nature of the atmosphere, especially the atmospheric water vapor, it is usually difficult to accurately model and correct the atmospheric effects. Consequently, significant errors are often resulted in InSAR measurements, especially in tropical regions like Hong Kong (HK). This paper studies a method for mitigating atmospheric effects on InSAR measurements based on an integrated use of Continuous GPS (CGPS) and ground meteorological observations. The tropospheric zenith delays (ZNDs) at a number of CGPS and ground meteorological stations in HK are first estimated and then used to construct a ZND map with a modified Kriging interpolator. Crossvalidation tests show that the mean value of the interpolation residuals is close to 0 and the RMS error is about 0.6 cm. When assuming a Gaussian distribution and under 95% confidence level, the interpolation errors are in range of –1.267 cm and 1.269 cm. The study shows that the temporal and spatial variations of the tropospheric ZNDs can potentially cause a peak-to-peak error in a SAR interferogram of about 9.36 cm at the 95% confidence level for a one-day interval. The error increases to about 11.47cm for a ten-day interval. When the interpolation results are applied to correct the atmospheric effects, the peak-to-peak errors are reduced to 7.50 cm and 9.19 cm respectively for the one-day and ten-day intervals. This shows a 20% reduction in the peak-to-peak errors.
منابع مشابه
The Double Interpolation and Double Prediction (didp) Approach for Insar and Gps Integration
The technique of synthetic aperture radar interferometry (or InSAR) was first suggested in 1974. Due to its characteristics of very high spatial resolution and wide coverage, as well as the cost effectiveness of the technique, it is not surprising that many earthquake ruptures have been studied using InSAR. However, InSAR is very sensitive to errors such as atmospheric effects, satellite orbit ...
متن کاملAtmospheric Effects on InSAR Measurements and Their Mitigation
Interferometric Synthetic Aperture Radar (InSAR) is a powerful technology for observing the Earth surface, especially for mapping the Earth's topography and deformations. InSAR measurements are however often significantly affected by the atmosphere as the radar signals propagate through the atmosphere whose state varies both in space and in time. Great efforts have been made in recent years to ...
متن کاملOn the accuracy of integrated water vapor observations and the potential for mitigating electromagnetic path delay error in InSAR
A field campaign was carried out in the framework of the Mitigation of Electromagnetic Transmission errors induced by Atmospheric Water Vapour Effects (METAWAVE) project sponsored by the European Space Agency (ESA) to investigate the accuracy of currently available sources of atmospheric columnar integrated water vapor measurements. The METAWAVE campaign took place in Rome, Italy, for the 2-wee...
متن کاملIntegration of GPS, Radar Interferometry and GIS for Ground Deformation Monitoring
Dense continuously-operating networks of GPS receivers (CGPS) have been established in many parts of the world in order to monitor ground deformation due to earthquakes and other activities. However, it has been found that the CGPS is still NOT dense enough to monitor some phenomena, e.g. volcano and ground subsidence due to mining. Therefore the authors propose to combine GPS with radar interf...
متن کاملEstimation of InSAR Tropospheric Delay Using ERA-Interim Global Atmospheric Reanalysis
Tropospheric delays are considered to be one of the main performance limitations for Interferometric Synthetic Aperture Radar technology when applied to ground deformation monitoring. In this study, we evaluate the performance of ERA-Interim global atmospheric reanalysis on estimating the tropospheric delay on Sentinel-1 InSAR observations. The results are validated by four D-InSAR interferogra...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2002