D. Petri

Passive ISAR With DVB-T Signals

As recently demonstrated, passive radars are able to detect and track targets by exploiting illuminators of opportunity. In this paper, it will be proven that the same concept can be extended to passive inverse synthetic aperture radar (P-ISAR) imaging. A suitable type of signal processing is proposed that is able to form P-ISAR images starting from range-Doppler maps, which represent the output of passive-radar signal processing. Multiple-channel digital television broadcasting (DVB)-T signals are used to demonstrate the concept as they provide enough range resolution to form meaningful ISAR images. The problem of grating lobes, which are generated by the DVB-T signal, is also addressed and solved.

Passive Bistatic Radar (PBR) for harbour protection applications

In this paper we investigate the feasibility of using Passive Bistatic Radar, PBR, to provide security for a harbour area. There have been numerous publications on the suitability of passive radar for air surveillance applications. However, this paper focuses predominantly on maritime applications. We investigate the ability of passive radar to detect, track, and eventually manage, marine vessels (boats). The paper includes a case-study of the Livorno Harbour in Italy. Livorno has been chosen as it represents a busy maritime hub. Simulations are provided to determine the theoretical radar performance, which are then compared with experimental results from a DVB-T-based passive radar. It will be shown that passive radars represent a viable solution for harbour protection applications.

DVB-T passive radar for vehicles detection in urban environment

Passive radar systems exploit non-cooperative transmitter to detect targets in areas of interest. Some of the main advantages of such systems with respect to conventional radars include low cost architectures, low energy requirements and potentially null probability of intercept. In this paper a low-cost solution for vehicles detection making use of passive radar concept is presented. A Software Defined Radio (SDR) solution and commercial antennas have been used to realize a DVB-T passive radar demonstrator. An analysis of the DVB-T signal is firstly presented together with a study of its capability as radar waveform. Afterwards an experimental setup is presented and analysed and finally some results of targets detection are shown.

Batches algorithm for passive radar: a theoretical analysis

Passive bistatic radar or passive coherent location is gaining interest in the radar community, as it provides some advantages with respect to active radar. Passive radar does not aim to replace active radar; it provides a good complement to it. The computational effort that is required to implement the required signal processing is one of the drawbacks that affect passive radars. In this paper, a suboptimal but computationally affordable detection algorithm is investigated that is applicable to arbitrary waveforms (different types of illuminators of opportunity). First, a detailed mathematical formulation of the proposed suboptimum algorithm is derived. A theoretical performance analysis is then provided based on a comparison of the proposed with the optimum two-dimensional matched filter. Finally, simulated and real data are used to demonstrate the effectiveness of the proposed algorithm and to validate the theoretical performance analysis.

High-range resolution multichannel DVB-T passive radar: aerial target detection

The exploitation of multiple DVB-T channels for a passive radar system has been considered to enhance the radar range resolution. A preliminary study has focused on the AF analysis to verify the suitability of a multichannel DVB-T signal for radar applications. The theoretical study has been supported by preliminary measurements relative to three adjacent DVB-T channels. Experimental results in an aerial scenario through the use of SDR hardware have been carried out and showed a clear improvement in range resolution when using multichannel rather than single channel DVB-T signals. It may be proven in the near future that target classification of noncooperative target radar imaging will be enabled by a high resolution DVB-T passive radar that is obtained by exploiting multichannel DVB-T signals.

The effects of DVB-T SFN data on passive radar signal processing

In this paper, we compare and contrast code, time and spatial domain signal processing techniques for mitigating the effects of the ambiguities present in single frequency network digital broadcast signals in passive radar. By performing these additional processing steps, the number of ambiguities present in the range Doppler scene will be reduced by approximately one third or a half (situation dependant). We also compare and contrast different combinations of temporal and spatial signal processing and demonstrate using real data that adaptive beamforming combined with temporal signal processing gives the greatest SINR performance.

Multifunction imaging passive radar for harbour protection and navigation safety

In a maritime domain awareness scenario, two main areas of interest can be recognized, specifically harbour protection and navigation safety. Harbour protection is currently a main concern and it is aimed at controlling the risk associated with possible attacks or illegal activities which can take place in the marine access areas. On the other hand, the objectives of the navigation safety are essentially connected to achieve an improved maritime navigational awareness by providing information on collision avoidance and general guidance to the navigators [1].

An integrated space-based passive system for maritime operational traffic surveillance

An integrated solution for the improvement of maritime traffic safety is proposed in this paper. Satellite and terrestrial-based data sources are fused to achieve a common operational picture for situational awareness. In particular, the system is composed of: 1)passive radars making use of DVB-T, DAB, and satellite broadcast transmitters for off-shore and coastal surveillance; 2) COSMO-SkyMedsatellites for large scale traffic monitoring; 3) Galileo positioning system for search and rescue services. Local and national authorities are the main potential users of such an integrated service.