ASHDOD, Israel — Drones are becoming an increasing threat to military and civilian infrastructure. Last month, a drone sighting disrupted flights at Britain’s Gatwick Airport for more than 24 hours, leading to the in-country deployment of the British Army. Operations at Newark Liberty International Airport in New Jersey were also disrupted for over an hour on Jan. 22 after reports of a drone sighting. In Iraq and Syria, the international coalition against the Islamic State group has faced a variety of threats from commercial off-the-shelf UAVs.
Elta Systems, a division of Israel Aerospace Industries, demonstrated a possible solution in January with the latest generation of its Drone Guard.
Unveiled in 2015, Drone Guard was built on adapted radar and electro-optical technology with the capability to detect low-signature and low-speed targets. Since then, hundreds of units have been sold to more than 10 countries. It was used by Argentina to secure a G-20 summit and the Youth Olympic Games last year. Elta said some customers have shown interest in guarding ships against drones, particularly when docked at a foreign harbor.
It was in November 2018 when Elta added a communications intelligence, or comint, system to the array that is more precise at detecting the frequencies of drones. The company also upgraded Drone Guard’s 3D radar as well as its electro-optical and jamming systems. While Elta makes the radar and jammers, it’s IAI’s Tamam Division that’s behind the electro-optical portion.
“We came early to this field and we were one of the first,” said Igo Licht, Elta’s vice president of marketing. “With all these asymmetric technology, you do one step and the enemy does another step; the system today is different than two years ago. In another year we will add additional features in [response to the] changing environment.”
At the demonstration, Elta set up a tent with a monitor and computer to view the environment covered by the radar. The system consists of three pieces of hardware on tripods: the rotating radar, a small electro-optical turret and the jammer. Together, the three pieces are lightweight enough to be transported by a pickup truck.
Drones can hover or hide behind structures, and dart among trees, making them difficult to distinguish from birds. This is why claims of drone sightings sometimes turn out to be inaccurate. Elta believes that by combining radar with an ability to visually monitor a target and detect its communication frequency enables controllers to accurately identify a drone threat. In addition, the jammer enables the operator to deactivate the drone.
“We have means to also take over the drone, to capture it. And there are situations where it is threatening and one can activate hard-kill solutions,” Licht said. The hard-kill option would be an add-on to the existing Drone Guard system.
IAI says Drone Guard’s open architecture allows for custom tailoring for a variety of applications — the reason the platform’s three parts remain separate.
Consider an airport that needs several jammers at different locations to minimize interference with other airport systems. The radar can be programmed to a defined mission area using its 360-degree range.
As Elta’s demonstration showed, when drones hover, their radar signature is reduced. But a red line on the monitor shows whether the comint system is still monitoring the drone communicating with its operator. Simultaneously, the drone can be visually examined. And when it comes time to jam the target, the jammer function also enables the operator to jam GPS.
At the demo, when Elta activated the jammer, the drone operator’s smartphone screen went dark as communication was severed.
According to Elta, the radar “can detect more than 200 targets, and the comint and jammer can detect dozens.” This allows for countering a drone swarm. The company also says its jammer doesn’t contaminate other channels and that its beam is directional based on channel type, enabling individual targets to be jammed without impacting others.
But what if an enemy’s military drones use encrypted communications, or can fly beyond Drone Guard’s range? Elta admits that Drone Guard is meant for dealing with small, slow drones that tend to have a lower endurance than their larger counterparts, and therefore the system has a detection range up to 20 kilometers, depending on the configuration. Elta says its 3D radars, “including the ELM-2026D, ELM-2026B and ELM-2026BF for short (10km), medium (15km) and long (20 km) ranges, respectively)," are used to detect low-signature targets.
Among other Israeli firms targeting the counter-drone market in recent years is Rafael Advanced Defense Systems with its Drone Dome, sold to the U.K. in 2018, and Elbit Systems' ReDrone, unveiled in 2016 and showcased at last year’s international air and space event FIDAE in Chili.