A covert, passive device designed to detect human activity independent of a physical obstacle is the “Virtual Fence” sensor array, combining acoustic, seismic and IR sensors to detect, locate, and identify human activity in a protected area. The system designed by EROD can operate passively under adverse weather conditions, in low visibility and under heavy electromagnetic disturbances. The system enables target detection beyond line of sight, such as movements of humans, vehicles and low flying helicopters hidden in ground defilades.
The sensors are installed underground, in sealed boxes containing digital signal processors and wireless communications devices, geophones, microphones, IR detectors and power sources. the only element above ground is a concealed camouflaged antenna. each sensor contains a processing unit which performs target identification (ID) and direction finding (DF). The IDDF algorithms enable monitoring and discriminating between diverse activities, such as moving humans, digging and building work, as well as mechanical noises such as approaching vehicles. The system can be implemented to provide early warning for border and perimeter control, tunnel excavation, protection of pipelines and electrical infrastructure, guarding vital installation perimeters as well as monitoring prison fences.