DVB-T Signal Ambiguity Function Control for Passive Radars

The use of digital video broadcasting-terrestrial (DVB-T) signals as waveform of opportunity for passive coherent location (PCL) is addressed here. The ambiguity function (AF) of the considered waveform of opportunity has been shown to yield regularly spaced undesired peaks which might strongly limit the target detection capability of a DVB-based PCL system. A new technique for DVB-T AF control is proposed, able to overcome the limitations of previously proposed approaches in terms of achievable performance, system requirements, and computational burden. The performance analysis against simulated and real data shows that the proposed technique yields an effective removal of the undesired peaks in the AF thus making the considered waveform more attractive for PCL surveillance

Impact of synchronization on the ambiguity function shape for PBR based on DVB-T signals

In this paper the use of Digital Video Broadcasting Terrestrial (DVB-T) signals is addressed for Passive Bistatic Radar (PBR). The impact of the synchronization accuracy is analyzed on the PBR Ambiguity Function (AF) shape in term of Peak to Side Lobe Ratio (PSLR), there including timing synchronization, frequency offset synchronization and frequency sampling offset synchronization. Different approaches proposed in the past are considered for the removal of the side peaks of the AF of DVB-T - based PBR. Their performance in the presence of synchronization errors are evaluated both by simulation and against a real data set collected by a PBR prototype developed and fielded at the INFOCOM Dept. of the University of Rome "La Sapienza"

Experimental results for passive bistatic radar based on DVB-T signals

In this paper the use of Digital Video Broadcasting Terrestrial (DVB-T) signals is addressed for Passive Bistatic Radar (PBR). The COTS (Commercial Off-The-Shelf) equipments to acquire the data, which are used to detect the potential targets, are described. The capability of a DVB-T based PBR system to detect both low flying aircraft and ground moving targets has been proved by experimental results. © 2013 German Inst of Navigation

DVB-T based Passive Bistatic Radar for maritime surveillance

In this paper we present a suitable receiving and processing chain for a DVB-T based Passive Bistatic Radar (PBR) system for maritime surveillance. The proposed PBR scheme is tailored for the maritime surveillance with specific attention to the detection of targets of limited size. The work is focused on the experimental results achieved in strong collaboration between Selex ES and the University of Rome 'La Sapienza'. Specifically, results are shown, that have been achieved in several test campaigns held in Civitavecchia and Livorno, with both cooperative and opportunistic targets equipped with the Automatic Identification System - AIS

A New Approach for DVB-T Cross-Ambiguity Function Evaluation

In this paper the use of Digital Video Broadcasting-Terrestrial (DVB-T) signals as waveform of opportunity for Passive Bistatic Radar (PBR) is addressed. A new approach for DVB-T Cross-Ambiguity Function (CAF) evaluation is proposed, which exploits a linear filter based on the knowledge of the expected value of the ambiguity function. The proposed approach is able to remove the unwanted deterministic peaks in the CAF due to specific features of the DVB-T signal, as guard intervals and pilots. The performance of the conceived filter is evaluated against simulated data and compared to other existing approaches. It is shown to yield more robust performance in terms of CAF improvement with reduced computational load and system complexity. © 2009 EuMA

A Flexible Receiver Architecture for Multi-Band Passive Bistatic Radar

In this paper a flexible receiver architecture is described for a Passive Bistatic Radar (PBR) that can exploit any of the many broadcast signals available in the frequency spectrum, going from the FM and VHF-UHF bands (DAB/DVB-T) to the S-band (WiFi/WiMax/LTE). Specific front-ends receiver sections are foreseen for each selected waveform of opportunity, while a common part of the system performs the I&Q demodulation and the Analog-to-Digital (A/D) conversion. The scheme can be used both for a direct I&Q conversion and for a double conversion (up-conversion stage from Radio Frequency-RF-to a high Intermediate Frequency-IF-and down-conversion from IF to Base Band-BB-) of the received signals for PBR applications. This allows to remove the image frequency even in the wide bandwidth occupied by the digital TV signals. A prototype of the proposed concept has been developed and fielded, with proper laboratory tests and real data acquisition campaigns, at DIET Dept. of the University of Rome 'La Sapienza'. The results obtained with the receiver, in three possible configurations, are reported and discussed: FM-based PBR (for medium/long-range air targets surveillance), DAB/DVB-T (for medium range air and sea surveillance) and WiFi-based PBR (for short-range human target localization). © 2013 EMA

Space-based passive radar enabled by the new generation of geostationary broadcast satellites

In this paper we investigate the possibility to develop a passive radar system for mid-range air target surveillance using, as illuminator of opportunity, a high EIRP level geostationary broadcast transmitter. These satellites are being introduced recently for Satellite Mobile Digital TV broadcast purpose. Since they are designed to allow mobile users to receive satellite TV without large antennas, a sufficiently high signal power is being transmitted, making them suitable as illuminators of opportunity in a passive radar system. The possibility to resort to a quasi-stationary transmitter is shown to highly simplify the signal processing required by the passive radar system. A preliminary evaluation of the achievable SNR is conducted, showing that mid-range target detection can be achieved with reliable performance. In addition, a detailed analysis of the Doppler frequency contributions is conducted. Specifically, the Doppler frequency contribution due to the motion between target and transmitter is shown to be locally independent over the target position. The overall bistatic Doppler frequency behavior is evaluated for several possible target trajectories and some critical trajectories are identified. Finally, some remarks referred to the 2D Cross Correlation Function (2D-CCF) evaluation are reported. ©2010 IEEE

Over the horizon maritime surveillance capability of DVB-T based Passive Radar

In this paper we explore the maritime surveillance capabilities of the Digital Video Broadcasting Terrestrial (DVBT) based Passive Bistatic Radar. Specifically we investigate the possibility to detect and localize vessels beyond the territorial waters since this represents a valuable characteristic for border security applications. The results are reported for the extended data acquisition campaign carried out in Leghorn (Italy). The low carrier frequency of the exploited waveforms is experimentally shown to allow maritime target detection at a distance from the coast much greater than the normal line-of-sight horizon. © 2014 European Microwave Association