In recent years, Synthetic Aperture Radar (SAR) technology has experienced remarkable advancements. SAR poses a significant advantage over other forms of remote sensing like All-Weather and Day-Night Imaging, which makes SAR ideal for monitoring regions with persistent cloud cover or areas where continuous monitoring is necessary. With polarimetry and interferometric techniques, SAR can provide valuable information about surface properties, vegetation structure, and terrain characteristics.

Initiatives like the sentinel -1 mission have made SAR data accessible to the public, allowing researchers, scientists, and professionals from diverse fields to benefit from this valuable resource. Open data policies promote collaboration, innovation, and the development of new applications that leverage SAR’s capabilities. Alongside government-backed missions, commercial players like Capella Space, ICEYE, Umbra have emerged in the SAR industry, offering high-resolution SAR imagery with quick turnaround times, thereby expanding the applications and accessibility of SAR imagery.

The future of SAR looks promising, upcoming missions like Tandem L by German Aerospace Center (DLR), Biomass by European Space Agency – ESA and NISAR jointly by NASA – National Aeronautics and Space Administration and ISRO – Indian Space Research Organization are expected to generate vast amounts of high-quality SAR data. These missions will not only enhance our understanding of Earth’s processes but also offer valuable insights for various sectors, including agriculture, forestry, climate monitoring, and disaster management.

Several government mapping agencies have shown interest in and utilising Interferometric Synthetic Aperture Radar (IfSAR) technology for terrain mapping and elevation data collection activities. IfSAR is a specific application of InSAR that focuses on mapping terrain elevation. IfSAR utilizes the principle of interferometry, which involves analysing the phase difference between radar signals reflected from the Earth’s surface. By comparing the phase of radar signals received from different positions, IfSAR can determine the surface elevation with high accuracy particularly in areas with dense vegetation or challenging weather conditions.

European Space Agency – ESA and German Aerospace Center (DLR) has been actively involved in the development and implementation of IfSAR technology and satellite missions such as TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurements). They have collaborated with other organizations to collect and process interferometric radar data for generating global elevation models.

U.S. Geological Survey (USGS) and Geospatial Information Authority of Japan (GSI) has utilised IfSAR technology for generating high precision elevation models.