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The interferometric Real-Aperture-Radar (RAR) technique consolidated in the last decade as an operational tool for the monitoring large civil engineering structures as bridges, towers, and buildings. In literature, data collected through a well-known commercial apparatus working at Ku band are well documented, while the cases where different sensors have been tested are a few. A radar interferometer is able to provide displacement samples of any structure with submillimeter accuracy, and from large ranges as distances radar target up to hundreds of meters, independently of the weather conditions and without any contact with the monitored structure; the main limitation is that only the component along the line of sight can be measured. Main performances are dictated by radar parameters as the swept bandwidth or the achievable SNR, which affect the range resolution, i.e. the capability to distinguish two different targets or parts of a surface, and the available accuracy respectively. On the bases of some basic experimental, a novel sensor working at a higher frequency, providing some improved performances is discussed. The core of the proposed system is an off-the-shelf, linear frequency modulated continuous wave (FMCW) K-band (centre frequency: 24 GHz) sensor. In fig. 1, a photo of the prototype is shown. This device can provide a lower maximum operating range with respect to the commercial available systems, but a better range resolution. The development of this sensor is devoted to a proof-of-concept aimed at tackling operative aspects, including a reduction of the costs. The data acquired through the radar are usually processed in two steps: the one necessary to transform the radar data to a range profile where we identity the different parts of the monitored target, based on a Fourier Transform, obtaining a range profile (see fig.2). The second step consists of the extraction of the phase temporal series and their spectral analysis, calculating for instance the power spectral density of the displacement story. The capability to detect the natural frequency of a light pole has been verified, and comparing the results of the novel sensor with those ones obtained through a commercial system, a more detailed description of the vibrating structure has been achieved. The analyzed sensor is very promising and deserves deeper studies and tests.