



NATIONAL HARBOR, Maryland—Anti-drone technology has been high on the shopping list of public safety and military organizations at least since a drunken federal employee crashed a drone onto the White House lawn. Two companies on hand at the Navy League Sea Air Space Exposition here this week had two slightly different approaches to the problem. One anti-drone device has already been deployed in the hands of federal law enforcement and the military, and a "street legal" version may be coming soon.

The drone "killer" getting the most attention at Sea Air Space was the DroneDefender, a system developed by researchers at the nonprofit research and development organization Battelle. DroneDefender is a two-pronged drone jammer—it can disrupt command-and-control signals from a remote operator or disrupt automatic GPS or GLONASS guidance, depending on which of the devices' two triggers is pulled.

Powered by a small backpack, DroneDefender looks like some futuristic over-under, radio-frequency shotgun-grenade launcher. Targeted through a simple optical sight, the device has a range of about 400 meters. Battelle calls it a "directed RF energy weapon"—it sends out a jamming signal in the Industrial, Scientific and Medical (ISM) bands or global positioning bands in a 30-degree cone around the point of aim.

Aboard the Department of Defense's Stiletto "marine demonstrator" boat, Jake Sullivan was showing off his company's own counter-drone "gun," the Dronebuster. Sullivan, chief technology officer of California-based Flex Force, said that his company began development of Dronebuster shortly after drones interfered with firefighters in California last year. The intent was to develop something for first-responders and local law enforcement.

A version of the Dronebuster is already in the hands of some federal government customers. That device uses broadband jamming like the DroneDefender. It has the advantage of being much smaller than the DroneDefender, and it can be aimed using optical sights or an integrated radio frequency power meter and signal analyzer. Someone trained on the device can even distinguish what kind of signal is being emitted from the drone—telemetry (such as remote video streaming) or control. Still, its jamming technology makes it illegal to use in the US.

But a new version being developed by Flex Force operates completely within FCC regulations, though depending on what kind of drone is targeted, the new device may require an FCC license. Instead of jamming C&C signals, the new Dronebuster exploits weaknesses in the drone communications protocols themselves, enabling the Dronebuster's operator to trigger the "fly home" command on some drones and the "land" command on others. It does so by cycling through command sets for various drone systems.

In the system currently being developed, GPS and GLONASS jamming are available through an add-on card available only to federal customers. Pending FCC approval of the product, Dronebuster could soon be made more widely available to local agencies and other customers.