Monitoring Strategies of Displacements and Vibration Frequencies by Ground-Based Radar Interferometry

In this work we present an overview of ground-based radar interferometry applications, using both real and synthetic aperture configurations, to measure deformations and vibration frequencies of infrastructures and terrain displacement due to geological phenomena. A short introduction to the basic principles of ground-based radar interferometry and the concept of interferometric coherence is provided. The interferometric processing of radar data provides the measurement of the Line-of-Sight (LoS) displacement with a sub-millimeter precision. In this paper we show results obtained in the monitoring of landslides, piers, dams, towers and bridges. Results have been obtained by means of a ground-based radar sensor working in the Ku-band with a range resolution of 0.75 m. Furthermore, we provide a review of literature on ground-based radar applications to volcano and glacier monitoring and measurement of vibration frequencies telecommunication and wind towers. The issues of measurement precision and artifacts due to propagation in the atmosphere are also discussed.