Filippo Parrini

Dynamic Monitoring of Bridges Using a High-Speed Coherent Radar

Remote dynamic monitoring of bridges by a high-speed interferometric radar is proposed. The equipment is a continuous-wave step-frequency radar with very fast frequency hopping that is capable of sampling the structure at a rate high enough for transient analysis of motion through phase comparison of successively acquired images. An experimental test carried out on a highway bridge forced by vehicular traffic is presented

Dynamic survey of architectural heritage by high-speed microwave interferometry

The authors propose the use of a high-speed interferometric radar for remotely measuring both transient displacements and steady-state vibrations of architectural heritage structures in order to test their stability conditions. Demonstrative results of application of the technique to a prominent cultural heritage artwork, the tower of Giotto in Florence, Italy, are reported.

An ultra-wideband high-dynamic range GPR for detecting buried people after collapse of buildings

An ultra wide band high dynamic range GPR radar - has been tested for buried victims detection. After a building collapse, for example due to an earthquake, the priority of search and rescue teams is to localize people trapped under debris. Several tools are available to help the detection of buried humans, such as micro-cameras, high sensitivity microphones, and so on. Many of these tools present some limitations such as low penetration depth and high susceptibility to external noises. In this paper the authors test the use of an Enhanced Ultra Wide Band (UWB), Continuous Wave Stepped Frequency (CW-SF) Ground penetrating radar as rescue equipment. The radar has been experimented both in controlled environment, and in a real test site, at the Fire-fighters Station of Pisa, Italy.

ULTRA: Wideband Ground Penetrating Radar

The frequency range employed in ground penetrating radar (GPR) systems is generally limited to 2 GHz because media loss increases dramatically at higher frequencies. Nevertheless, a series of applications exists in the Cultural Heritage field where the development of high frequency systems would significantly benefit, in terms of resolution, from an increased operating band. This article presents ULTRA, a wideband GPR (800 MHz-4000 MHz) system, using a CW-SF technique developed for this type of surveying

A reconfigurable stepped frequency GPR (GPR-R)

Ground Penetrating Radars are a unique and well known tool for soil investigation.

ORFEUS GPR: a very large bandwidth and high dynamic range CWSF radar

A very large bandwidth and high dynamic range Continuous Wave Step Frequency (CWSF) Ground Penetrating Radar (GPR) has been developed with the aim to increase the detection capabilities with respect to current systems . In order to achieve this goal, an innovative electronic equipment have been designed and developed. This radar operates with ultra wide bandwidth, ultra fast scan and very high dynamic range capabilities.

A novel ground based multi bistatic radar for interferometric measurement of displacement vector

A novel ground based multi bistatic interferometric radar sensor has been realized in order to measure the three dimensional displacement vector of civil structures as buildings, bridges and towers.

A Clutter Canceller for Continuous Wave GPR

In this work an innovative clutter canceller for Continuous Wave GPR (Ground Penetrating Radar) has been designed and implemented. An IQ modulator has been used to build up the central part of the device. The IQ modulator replaces more expensive components like digital controlled phase shifters and attenuators. This device also have wider dynamics with respect to linear vectorial modulator. To prove the feasibility of the system, the effect of signal feedthrough for IQ modulators is studied. Tests and measurements of the complete device are exposed.

Mitigation of narrowband interferences by means of a reconfigurable stepped frequency GPR system

This paper proposes a new technique for the mitigation of narrowband interferences by making use of an innovative stepped frequency Ground Penetrating Radar (GPR) system, based on the modulation of the integration time of the harmonic components of the signal. This can allow a good rejection of the interference signal without filtering out part of the band of the useful signal (which would involve a loss of information) and without increasing the power of the transmitted signal (which might saturate the receiver and make illegal the level of transmitted power). The price paid for this is an extension of the time needed in order to perform the measurements. We will show that this necessary drawback can be contained by making use of a prototypal reconfigurable stepped frequency GPR system.

An ultra high resolution stepped frequency GPR for civil engineering applications

In this paper the authors present an ultra high resolution and high dynamic range stepped frequency continuous wave radar for masonry investigations. The radar architecture is based on a couple of VCO in a PLL loop and a low noise receiver. This approach is able to cover with 801 steps the 4-8 GHz frequency range obtaining a theoretical range resolution of 37.5 mm in air and a dynamic range higher than 110 dB. The system has also a set of horizontal and vertical antennas to provide a complete polarization matrix of the investigated surface. Moreover the radar is completed with a 2 dimensional and fully automatic scanning system.