The Potential of Coherent Radar to Support the Monitoring of the Health State of Buildings

The investigation here described is aimed at evaluating the actual capability of a Real Aperture Radar (RAR) interferometer to detect the natural vibration of urban buildings solely solicited by wind or environmental noise. The paper shortly reviews some of the most relevant non-contacting measurement techniques that can be employed for ambient vibration testing. Then it introduces the proposed RAR measurement technique. Some experimental results taken from a wide set of observations, carried out through a microwave sensor presently available on the market, are discussed. The main factors affecting the measurability of the vibration amplitude and frequency are singled out. The technique is proved to perform high sensitivity displacement measurements, down to a few microns.