Multi-Band Passive Radar Imaging Using Satellite Illumination

Over the last years the interest has grown over imaging capabilities of passive radars, [1] [2]. In particular, the MAPIS (Multi-chAnnel Passive ISAR for military application) project funded by EDA (european defence agency) has shown the potential of ISAR imaging using passive radars based on different illuminators of opportunity, [3]. The results of MAPIS ([4]) demonstrated also how the obtained ISAR images can be effectively exploited for target classification and recognition [5] despite the limited range resolution. The main limitation of DVB-S-based radar imaging resides in the need for cueing the system to look in the direction where the target is. This is due to the limited power budget available in the DVB-S case and in the subsequent need for highly directive pencil-beam antennas. In this paper, the idea of passive radar imaging is further developed by proposing a multi-band passive radar system. In the proposed approach, target detection and imaging are considered two different tasks to be performed by two separate sub-systems: namely a cueing sub-system and an imaging one. The cueing subsystem is devoted to target detection, localisation, and mostly important it triggers and cues the subsequent DVB-S sub-system for target imaging. Different potential cueing sub-systems are investigated like other passive radars (based on FM, DVB-T, or other satellite communication signals) or passive emitter tracking (PET). This paper presents the system concept, and it proposes a potential experimental setup based upon hardware available at Fraunhofer FHR.