Interferometric synthetic aperture radar(InSAR)is greatly affected by ionospheric delay,especially at low and high latitudes,which decreases the number of available interferometric pairs for time-series InSAR and the monitoring accuracy of low-frequency SAR systems.To this end,the reformulating range split spectrum interferometry(RRSSI)was introduced for the ionospheric error estimation and correction in time-series InSAR.The performance of the proposed method was tested by ALOS-1 PALS AR images covering the Anaktuvuk River area in Alaska from June 2006 to August 2010.The experimental results show that the proposed method can effectively estimate the ionospheric errors of time-series InSAR results and is sensitive to ionospheric disturbances at small spatial scales.After correction,the average annual deformation rate in the study area decreases from 1.46 to 0.49 cm/year,and the standard deviation from 1.16 to 0.65 cm/year,indicating an improvement in monitoring accuracy.Additionally,the cumulative deformation of the selected time-series points becomes more stable than the large fluctuation before correction,which is more consistent with the real deformation.
关键词
小基线集-InSAR/电离层校正/距离向分谱法/时序
Key words
SBAS-InSAR/ionospheric correction/range split spectrum method/time series
维普
万方数据