Maritime moving target detection technique for passive bistatic radar with GNSS transmitters

The paper puts forward a moving target detection technique for passive bistatic radar systems based on GNSS signals for maritime surveillance applications. If from one hand navigation satellites are extremely attractive as opportunistic sources for passive radar due to their global coverage and the availability of multiple satellites, on the other hand they provide a restricted power budget. To strengthen the target energy sufficiently to allow its detection, observation time has to be increased up to several tens of seconds. This requires the need to develop innovative techniques able to deal with such long integration times. In this paper, a local plane-based maritime moving target detection (M-MTD) technique is proposed. Such a technique performs the integration of the received signal for a long integration time, properly taking into account the migration of the moving target during the entire dwell time. Moreover, it provides target detection in the local plane that represents the section of maritime area covered by the radar antenna. Since this plane is common to multiple transmitters, the proposed technique can be easily extended to the multistatic case, which is the bigger benefit in using GNSS sources. Simulated and experimental results confirm the effectiveness of the proposed M-MTD technique to detect ship targets, not detectable with conventional MTD techniques, with the GNSS-based passive radar.