Fusion of UHF-SAR with lidar elevation for precise buried object detection

The UHF band in SAR has foliage penetration and limited ground penetration capability, while LIDAR scans are capable of providing elevation information of objects on the terrain. In this paper, we integrate the complementary strengths of these two different classes of sensors to locate buried objects with improved precision. The main underlying concept is that the buried targets are discernible only in UHF-SAR space while LIDAR is rich with above-ground False Alarm information. The LIDAR elevation information at the changes and anomalies are exploited to rule out above-ground false-alarms in the UHF-SAR domain, thereby isolating the buried IEDs. Definitive proof-of-concept validation is given for same-day/single-pass buried object detection capability using single-pass SAR anomaly detection with LIDAR fusion. We also demonstrate significant performance improvement with 2-pass SAR change detection with LIDAR integration. Detection performance is further enhanced via exploitation of multiple polarizations and multiple passes for SAR data. The proposed SAR-LIDAR fusion strategy is shown to detect emplaced buried objects with an order of magnitude improvement in detection performance, i.e., achieve higher PD at lower PFA when compared with SAR-only performance. The proof-of-concept research is demonstrated on simultaneous multisensor UHF-SAR/LIDAR data collected under JIEDDO's HALITE-1 program.