The U.S. navy is testing and planning a large-scale installation of jamming weapons

The AN/ALQ-99 Tactical Jamming System is currently integrated on the EA-18G GROWLER and EA-6B Prowler aircraft operated by the US Navy and Marine Corps. Both aircraft are currently in service, but only the F/A-18G is expected to be in service beyond the mid 2020s. Therefore, the new pod is developed exclusively for the Growler.

“These systems consist of a satellite armed with a weapon such as an explosive charge, fragmentation device, kinetic energy weapon, laser, radio frequency weapon, cell phone jammer or robotic arm,” read the report.

The jammers “had a pretty significant impact” on UN surveillance drones, which were grounded for days after gathering intelligence from the air. American military officials would not say whether the latest jamming has caused drones to crash, citing operational security.

So far, the attacks have only affected small surveillance drones, four officials told NBC News, not the U.S. Air Force’s armed Predator and Reaper models. They declined to discuss whether any of the small aircraft had gone down as a result of jamming. High-end drones like the Global Hawk, Predator and Reaper are equipped with inertial navigation systems, which do not depend upon external signals for positioning, in addition to their GPS receivers.

The radio frequency jamming can be activated automatically upon UAV detection or manually upon supervisor assistance. The robust antenna system consists of circularly polarized antennas (the number of antennas depends on the number of frequency bands).

The drone signal jammer gun is based on detection and jamming units. The system scans for drones by using an array of directional antennas.

Once a threat is detected, the system sends an automatic command to the jamming unit and starts to block all radio communication channels, including GPS signals and video link.

Put simply, a jammer broadcasts noise such that GPS receivers in their vicinity — which rely on weak signals from distant satellites — are overwhelmed and lose the actual GPS signal. If a precision-guided bomb, a minute away from hitting its target, loses the lock, the results could be disastrous.

But the sources told NBC that Russian’s sophisticated jamming equipment, which was developed by its military, has proved to be effective even against some encrypted signals and anti-jamming receivers.