DARPA to Seek Underground Targets with Laser, Gravity Sensors


Raytheon is developing a new laser-assisted sensor system to demonstrate the detection and location buried land mines and tunnels. The system developed under a $19 million contract from the Defense Advanced Research Projects Agency (DARPA), will utilize a laser radar vibration sensor, (also known as LADAR vibrometer) to detect underground targets by measuring the reverberation of the ground-surface in response to artificial stimulus (vibration), measuring the anomalies created by underground objects or activity.

The integration of different sensors (Laser Vibrometer, acoustic and seismic) into a single system will provide to stand-off detection capability, with improved probability of detection while reducing false alarm rate. The LADAR vibrometer will provide the broad area sensor, capable of scanning a large area employing multiple parallel channels yielding 600 simultaneous pixels of data. This data will be enhanced and processed with acoustic and seismic data, constantly compensating for vehicle, and ambient noise created by structural and acoustic sources.

The system will employ Raytheon’s most advanced Morphable Networked Micro-architecture (MONARCH) processor, the world’s first computer whose architecture can adopt different forms depending on the application. The MONARCH is designed to flexibly allocate computing power to simultaneously process multiple, massive data streams, and efficiently handling large volume of data throughput by power efficient architecture, typical for mobile applications.

Under a different program, DARPA will study an airborne surveillance system designed to detect underground targets by spoting gravity-based effects from tunnels and underground facilities from the air. DARPA’s Gravity Anomaly for Tunnel Exposure (GATE) program will demonstrate the capability to map tunnel networks generated by aerial surveillance of gravity anomalies measured by ‘gravity gradiometer’ to detect, classify and characterize subterranean threats. The sensor will be designed to detect underground voides typical of tunnels, bunkers and caches, which can be traced by their characteristic gravity effects. The sensor will be designed to measure minute spatial variations in the pull of gravity caused by the voids. Installed on a low-flying aircraft or UAV, the GATE sensor will try to detect those variations and process the signals on-board, in near real-time, to discriminate the positive signal from the variable natural and man-made topography and geology.