11:50 AM - 12:05 PM
[STT59-11] Persistent scatterer SAR interferometry using multi-polarimetric SAR interferograms
Keywords:persistent scatterer SAR interferometry, surface deformation, polarimetry
Persistent scatterer SAR interferometry (PS-InSAR) is a method to estimate surface deformation using a number of SAR interferograms, and has been applied to aseismic fault slip, volcano and land subsidence as a practical monitoring tool. In recent years, more and more satellites that are equipped with SAR, which can acquire multi-polarimetric data has been operated. In this study, we propose a method to processing PS-InSAR analysis using multi-polarimetric SAR interferograms, and show that the estimation accuracy of surface deformation increases.In this study, we increase estimation accuracy by processing multi-polarimetric SAR interferograms simultaneously. Since, the amount of noise ratio would differ in different multi-polarimetric SAR interferograms depending on the geometry or electro-magnetic characteristics of targets, we determine the weighting coefficient between polarimetric SAR interferograms from observed phase based on maximum likelihood method. We applied the method to ALOS/PALSAR data acquired in multi-polarimetric mode. First, we processed HH-HH and VV-VV interferograms simultaneously. As a result, weighting of HH-HH and VV-VV interferogram was almost identical, suggesting that decorrelation-induced noise in HH-HH and VV-VV interferograms was almost same. In this case, the accuracy of estimated deformation rate would increase twice. On the other hand, when we processed HH-HH and HV-HV interferograms simultaneously, the weighting of HH-HH interferograms are larger than that of HV-HV interferograms, suggesting that HH-HH interferograms has less amount of noise compared with HV-HV interferograms. Nevertheless, we found that the estimation accuracy increases by using both HH-HH and HV-HV interferograms compared with the standard analysis using HH-HH interferograms.