Small drones now present a major threat for security forces, not just to high-profile events and public figures, but also to infrastructure and city centres.
While this has spawned a rise in the number of counter-UAS systems being developed, one of the main challenges remains the detection and tracking of small vehicles, particularly in urban areas where drones would typically follow the street pattern to stay below rooftop height, rendering traditional area surveillance largely ineffective.
Thales (External Stand A690) is addressing the challenge of tracking drones in such an environment through its Smart Sensor Grid system, which is currently in development. This merges data from a wide range of available sensors, such as low-cost roof-mounted cameras, short-range radars, passive radars and visual observations, and presents it on a 3D grid of the area of interest in a control centre. Individual sensor coverage can be hampered in a city environment by buildings, but the limitations of each sensor are also plotted on the display.
Advanced moving-target image processing in the system allows the drone to be detected against cluttered backgrounds that would make the drone virtually impossible to spot with the naked eye. Detection of a potentially malicious drone by any means initiates a tracking process, with a plot of the vehicle’s movements shown on the grid display. The track is handed over from one sensor to another as the vehicle moves through the city. If the drone flies into an area where there is no sensor coverage, the system predicts its possible trajectory, based on the street pattern, to provide a number of points where other sensors will pick up its track.