Ricerc@Sapienza

An important field of application of Forward Scatter Radar systems (both single-node and multi-node) consists in the estimation of the target kinematic parameters. In the past different studies have shown the possibility to extract these parameters by estimating the main target signal parameters (i.e. Doppler rate, derivative of the Doppler rate) and the time instant at which the target crosses the baseline. The estimation accuracy of the motion parameters depends on the estimation accuracy of the target signal parameters and on the FSR geometry.

In this paper, Principal Component Analysis technique is applied on the signal measured by an ultra wide-band radar to compute the breath and heart rate of volunteers.Themeasurement set-up is based on an indirect time domain reflectometry technique, using an ultra wide-band antenna in contact with the subject’s thorax, at the heart height, and a vector network analyzer.The Principal Component Analysis is applied on the signal reflected by the thorax and the obtained breath frequencies are compared against measures acquired by a piezoelectric belt, a widely used commercial system for respira

Passive Bistatic Radar (PBR) systems use noncooperative illuminators of opportunity to detect, localise and track targets. The aim of this paper is to investigate the potential of PBR target detection in the presence of non-random signals emitted by non-cooperative transmitters of opportunity, such as radar systems, and without the use of a reference channel. An experiment to detect a moving target was carried out at the Defence Academy of the United Kingdom to demonstrate target detection capabilities using a low cost off-the-shelf receiver.

This study investigates the potential advantages conveyed by the exploitation of polarimetric diversity in Passive Coherent Location (PCL) system exploiting Digital Video Broadcasting - Terrestrial (DVB-T) signals. To this purpose, different polarimetric detection schemes are considered that jointly exploit the signals collected at different receiving channels characterised by differently polarised antennas. A performance analysis has been carried out using experimental data collected by a passive radar system developed by Fraunhofer, namely PARASOL.

The focus of this paper is the evaluation of the mono-static Radar Cross Section (RCS) of a commercial Drone (IRIS) through both simulation and measurements in the 1-4 GHz frequency range. In particular, for the simulations an approximate model of the drone geometry and its material complex permittivity was carried out by means of an electromagnetic CAD. Most importantly, measurements have been performed in an anechoic chamber equipped with a network analyzer and a horn antenna. The obtained results show RCS values between-18 dB and-1 dB in the 1-4 GHz frequency range.

We propose a compact circularly polarized series-fed patch array with enhanced radiation performance at S -band. To our best knowledge, no similar single-layer structure has been designed, measured, and reported in the literature with equivalent radiation performances in terms of reduced sidelobe level (SLL) and aperture efficiency as well as compactness and simplicity. The planar array consists of a 50- Omega microstrip single feed point, offering uniform and efficient excitation of all its elements that enable a broadside beam with high-gain and low sidelobes.

We apply the formalism of functional integration to the calculation of the transfer function of a stochastic scattering channel formed by stationary, non-interacting point scatterers. The channel is described through a scattering amplitude density, defined over space, whose random component is characterized by a functional probability distribution. This random component induces in turn a probability distribution for the scattering transfer function, which we compute by means of functional integration in the case of Gaussian distributions.

Recently, the Cassini RADAR was used to sound hydrocarbon lakes and seas on Saturn’s moon Titan. Since the initial discovery of echoes from the seabed

The Cassini RADAR altimeter has provided broad-scale surface topography data for Saturn's largest moon Titan. Herein, we adapt the delay/Doppler algorithm to take into account Cassini geometries and antenna mispointing usually occurring during hyperbolic Titan flybys. The proposed algorithm allows up to tenfold improvement in the along-track resolution. Preliminary results are provided that show how the improved topography presented herein can advance our understanding of Titan's surface characteristics.

Radar-based snowfall intensity retrieval is investigated at centimeter and millimeter wavelengths using co-located ground-based multi-frequency radar and video-disdrometer observations. Using data from four snowfall events, recorded during the Biogenic Aerosols Effects on Clouds and Climate (BAECC) campaign in Finland, measurements of liquid-water-equivalent snowfall rate S are correlated to radar equivalent reflectivity factors Ze, measured by the Atmospheric Radiation Measurement (ARM) cloud radars operating at X, Ka and W frequency bands.