Testing Polygon for Simulated Vertical Displacement Measurements based on Co-located InSAR Corner Reflector and GNSS Station

Abstract

With the growing availability of accurate and long-term measurements of displacements of technical infrastructure elements, there is a growing interest in the automated processing of acquired data. Various methods can be used for monitoring; however, radar interferometry and Global Navigation Satellite Systems (GNSS) measurements are among the best for long-term monitoring. GNSS allows for continuous monitoring of individual points, while radar interferometry allows only periodic data collection but with an areal coverage. Radar interferometry can also reach a better precision under certain conditions; therefore, it appears to be more appropriate. Automated systems are being developed that allow not only to process radar data but also to detect anomalies in vertical displacement. It is advisable to have a testing polygon for their verification, enabling the comparison of the automated processing of radar interferometry with an independent GNSS measurement. In autumn 2019, a testing polygon was built at the Department of Geoinformatics, HGF VSB – Technical University of Ostrava, consisting of three corner reflectors. Two are fixed, but one, complemented by a GNSS receiver, has an adjustable height. The article describes its construction and presents the first results of comparing automated radar interferometry processing with GNSS measurements.

Keywords: Corner reflector; Corner reflector and GNSS receiver co-location; Displacement monitoring; GNSS; InSAR; PS-InSAR; Sentinel-1; Testing polygon; Vertical displacement.