At a small brewpub in Užupis, a hip neighborhood in Vilnius, Lithuania, hangs a portrait of a Madonna-like saint cradling a weapon—something between a rifle, a bazooka, and a 5G antenna. The caption below reads: “Saint EDM4S.” EDM4S—or Electronic Drone Mitigation 4 System—is a portable electronic-warfare weapon from Lithuania. Point the EDM4S at a hovering uncrewed aerial vehicle (UAV) and pull the trigger: The drone should lose contact with its operator and fall inertly from the sky. Hundreds of EDM4S systems have been donated to Ukraine over the past two years. They are just one weapon in an unseen, and under-appreciated, battle for control of the electromagnetic spectrum. Powering this battle is a furious arms race. Ukraine and its allies on one side, Russia on the other. Both sides are trying to innovate better ways to spoof, jam, and disrupt enemy communications, particularly drones, while simultaneously working to harden their own systems against hostile signals. This is electronic warfare. In late 2023, Kyiv identified winning the upper hand in this battle as one of its key priorities. With Russia steadily advancing across eastern Ukraine, the need to gain control of the electromagnetic space—and the skies—has only grown more important. Regardless of how this war unfolds in 2025, Ukraine has already changed electronic warfare forever.
Electronic warfare, or EW, has been a part of human conflicts for more than a century. Soon after radios were deployed to the battlefield, soldiers realized that sending bursts of static over a frequency could disrupt the enemy’s ability to communicate. But it wasn’t until World War II that EW really came into its own. Early in WWII, the British were desperately trying to recapture control over their skies in the Battle of Britain. While British dogfighters grew steadily better at downing incoming Luftwaffe bombers, the Germans slowly moved their raids to the cover of darkness. This prompted a perplexing mystery for the British: How were the Germans so good at flying to their targets in the dead of night?
A young British scientist solved the mystery when he discovered a clue in the wreckage of a downed bomber. The plane’s landing assistance system, which used radio waves to measure the plane’s relative distance to the runway, had been improved so dramatically that it was being used as a rudimentary navigation device. Operators on the ground in Germany and occupied France would emit long, narrow bands of radio signals over British skies: The target factory or town could be found where the two beams coincided. Armed with this information, the English raced to build their own radio and relay stations, broadcasting their own radio beams into the skies to confuse the incoming German pilots.
Thus began the Battle of the Beams. The Germans refined and upgraded its ability to broadcast and receive signals in British airspace, while the United Kingdom rapidly developed its own countermeasures. This back-and-forth struggle for control of the electromagnetic spectrum has continued to this day, with both sides constantly seeking new ways to gain an advantage over the other. In the current conflict between Ukraine and Russia, electronic warfare has become a crucial component of the battle for control of the skies. As the war unfolds, it is clear that Ukraine has already made significant contributions to the field of electronic warfare, forever changing the way it is waged.
