11. Synthetic Aperture Radar Interferometry

In the past two decades INSAR technique (synthetic aperture radar interferometry) has been quickly developed and widely used for the study of topography (digital elevation model generation) and deformation (Earth surface monitoring). Synthetic aperture radar (SAR) is a coherent active microwave image instrument, which is used for mapping the scattering properties of the Earth’s surface in the respective wavelength domain. The intensity (grey value) of each pixel in an SAR image represents the physical and geological property and geometric parameters of the imaged scene. In the late 1970s the first space-borne SAR system in the world (NASA satellite SEASAT) was launched for Earth observation. This mission pioneered the application of the SAR technology to mapping the Earth’s surface, acquiring information about physical and geological properties such as topography, morphology, moisture, and finding underground water. The space-borne SAR systems operate in the microwave range and therefore work on all days and all meteorological conditions.