Assessment of Displacement Measurements by a mmWave Radar

Radar vibrometry is a promising technique to measure the vibration of a target through an electromagnetic signal. The capability of a Radar to detect and measure a target vibration is well-known in literature, but an analysis of the attainable performances from a metrological point of view is necessary to understand how such a technology can be used in practical applications. Fields in which this technique can be of interest, are for example vital parameters monitoring or civil applications such as bridges vibrations measurements. The quantification of the performances in these cases is crucial to choose the best measurement technique. In this work, vibrational signals are extracted from a mmWave Radar and the results are compared to those obtained with a reference Laser Vibrometer, to evaluate the attainable performances. The focus of the investigation is not only on the measured displacement amplitude and frequency values but also on the capability to reconstruct the time evolution of the displacement signal itself. The results will show how the measurement error can be calculated and also the mean error and their distribution will be presented.