Persistent Scatters Interferometry (PSI) is a state of the art technology using radar images to monitor deformations of the Earth surface that is of high interest in monitoring activities in Earth Observation, because it provides high accuracy, combined with other advantages, as large area covering, long periods of time monitoring possibilities and cost efficiency on long term.

Several companies offer, at international level, operational PSI monitoring services, but only few are validated PSI providers, according to Terrafirma standards.

Terrafirma is an ESA GMES project that supports the process of risk assessment and mitigation by using latest technology for measuring terrain motion from satellite radar data. Among other activities, it offers PSI providers the opportunity to undergo the Terrafirma PSI validation procedure in cooperation with DLR. The scope of the validation procedure is to determine the PSI accuracies and reliabilities in given circumstances, to prove the validity of the PSI processing concept, and, in the end, to earn the end users’ confidence in monitoring service using PSI.

After successful completion of all necessary technical steps, at the end of 2014, TERRASIGNA (former ASRC) has become the first East - European validated PSI service provider, with Terrafirma and DLR active support. Infrastructure stability of nuclear facilities, ground subsidence from brine extraction in a mining area, waterdams and slopes stability, slopes and infrastructure stability along the Danube river, water level variation and coastal erosion in wetland areas, toxic sludge retention ponds in inactive mining areas, ground stability in an area affected by strong tectonic activity are monitored within services developed by TERRASIGNA using PSI technology.

Since its establishment in 2007, TERRASIGNA is the only Romanian company that developed in-house capabilities of analysis, processing and interpretation of optical and radar Earth Observation data. It provides customized Geo-Information services to a wide pool of public and private national, European and North American clients.

TERRASIGNA validation as PSI service provider represents an important recognition of its capabilities and expertise to be engaged in future projects with strong European impact.