An Improved R-Index Model for Terrain Visibility Analysis for Landslide Monitoring with InSAR

The interferometric synthetic aperture radar (InSAR) technique is widely adopted for detecting and monitoring landslides, but its effectiveness often degraded in mountainous terrains, due to geometric distortions the (SAR) image input. To evaluate terrain effect on applicability of InSAR landslide monitoring, a variety visibility evaluation models have been developed, among which R-index are quite popular. In consideration poor performance existing passive layover region, this study presents an improved model, coefficient improving far regions incorporated. demonstrate SAR images Fengjie, county Three Gorges Reservoirs China, studied. model demonstrated through comparing results with those obtained from P-NG method. Further, effects line-of-sight (LOS) parameters resolution digital elevation (DEM) discussed.