The silent electronic battleground shaping the future of warfare

Summary

From spoofing hypersonic missiles to jamming drone signals, combat zones are in the grip of an electronic arms race.

KYIV, Ukraine -- Earlier this year, two Russian ballistic missiles hurtled at hypersonic speeds toward a key government site in Ukraine's capital city. They crashed into the Dnipro River after being intercepted by a radio signal.

Around that time, the navigation apps on many phones in Kyiv showed users as located in Peru. It was the electronic calling card of Night Watch, an elite Ukrainian jamming unit that says it downed the missiles with its Lima system.

A silent electronic battle is raging at the heart of the Russia-Ukraine war. Both sides are attacking and defending communication signals on an unprecedented scale, innovating at pace, while the U.S. and other Western countries are working to catch up. The Pentagon is investing heavily in new capabilities.

"This is a new era of spectrum warfare," said Lt. Col. Matt Sherburne, the U.S. Army's chief for electronic warfare capabilities development.

Electronic warfare isn't new, but it fell out of focus in the West after the end of the Cold War. Then came Russia's war on Ukraine, where swarms of drones have become the dominant weapon on the front lines. Both sides are now engaged in a constant game of cat and mouse, jumping around the frequency spectrum to jam and avoid each other, and they are increasingly using AI to do that.

Electronic warfare is already reshaping the battlefield. The U.S. began its operation to grab former President Nicolás Maduro by using electronic warfare to knock out the ability of the Venezuelans to see and communicate. The Iran war saw the first deployment of the U.S.'s new signal-jamming jet, the EA-37B Compass Call.

Also known as spectrum warfare, EW essentially relies on finding or disrupting the frequencies that adversaries are using, or hiding signals from enemy interference. At its simplest, that works by blasting signals to drown out, confuse or supplant an adversary's communications.

Ukraine's Night Watch division uses Lima to blast signals over a 120-mile range that disrupt drones, missiles and guided bombs, said a major in the unit, known by his call sign Alchemist. The unit used Lima to confuse the ballistic missiles that crashed into the Dnipro, filling the air with false signals -- a technique known as spoofing.

Last November, Night Watch claimed one of its biggest scalps when it intercepted a hypersonic Kinzhal missile, once dubbed invincible by Russian President Vladimir Putin. Lima beamed a false navigation signal at the missile, prompting it to alter direction and break up under the pressure of its own extreme speed, according to Night Watch officers.

Ukraine won't say how often electronic warfare, rather than in-flight failure, is responsible for downing missiles and drones. It can be hard to tell the difference. Electronic interference can unintentionally divert a target to civilian areas.

Ukrainian officers say that Lima can sometimes interfere with their own drones amid operations.

Still, they are in no doubt of how effective electronic warfare is. One officer for Ukraine's Unmanned Systems Forces said it suppresses 70% to 95% or radio-controlled drones detected in the sector where his team operates.

Phantom Defense, a Ukrainian manufacturer, says that over the past year of operation, its systems detected more than 11,500 Russian drones, of which around 7,500 were successfully neutralized, with confirmed results via the video feeds from the drones, which the company also intercepts.

And Ukraine is buying vast amounts, underscoring the success. Ukrainian firm December1 now sells thousands of its front-line and long-distance units a month, up from dozens in 2024.

Ukrainian manufacturer Phantom Defense takes over the footage of Russian drones and intercepts them with electronic warfare.

Since the start of the 20th century, when the British Royal Navy experimented with radio jamming and intercepting enemy communications, the vulnerability of radio signals has been exploited in combat. It truly took off in World War II, when the U.K. and Germany jammed and spoofed aerial navigation signals in what Winston Churchill dubbed the battle of the beams.

As military communications and radar became more sophisticated during the Cold War, so did the technology to interfere with them.

But in post-Cold War conflicts, the U.S. faced lower-tech adversaries in Afghanistan and Iraq. Further advances in electronic warfare were less of a priority for the Pentagon. U.S. officials say Russia's invasion of Ukraine has been a wake-up call.

Joshua Ransford never worried about electronic warfare when he served as a U.S. Marine in Iraq, because America's adversaries had such little capability in this field. Later he joined the international legion of Ukraine's armed forces in 2022, after Russia launched its full-scale invasion.

In his first days of fighting, Russian forces jammed his GPS signals and radio frequencies, rendering much of his equipment useless. The enemy flew drones that could find Ukrainian positions by sniffing out their electronic emissions, including radio.

"It really sucked," Ransford said.

Today's networked world offers jammers more targets than ever, from cellphones and satellite navigation systems to a plethora of new guided weapons and drones, as well as traditional radio and radar. By 2022, electronic warfare was one of the Pentagon's top three procurement priorities, along with long-range munitions and affordable technology, for countering drones and missiles, according to Bill LaPlante, who was the Biden administration's top procurement official.

China, too, is expanding its capabilities. Military analysts, for instance, say it has established electronic warfare units on an archipelago of man-made islands in the South China Sea.

As the U.S. and Europe also boost spending, spectrum warfare has become one of the most lucrative fields for Western defense companies. Hot items include pods tethered to ships and planes that replicate the electronic signature of the vehicles they trail and act as a decoy for missiles and torpedoes; drones that sniff out an adversary's electronic emissions; and equipment that alters radar pulses to confuse the enemy.

The battle to work around the jammers is similarly intense.

Naval vessels sometimes communicate with other ships via lasers that can't be jammed. Russia and Ukraine are using fiber-optic cables to connect drones directly to their operators. Both sides have artificial intelligence-enabled drones that can lock onto and destroy targets without needing a feed to a pilot.

All these methods have shortcomings. Lasers only work over small distances and in good weather. Fiber-optic drones are slower and less maneuverable. AI has some way to go before drones can reliably navigate terrain over long distances on their own, said Vito Tomasi, a managing director at German drone maker Quantum Systems.

In the meantime, Night Watch is pedaling hard to stay ahead.

On a balmy August day, six Lima antennas shaped like megaphones pointed skyward from poles on the edge of a field in a rural part of Ukraine. The antennas blast out electromagnetic signals generated by computers connected to the poles and housed in protective cases.

A soldier received an air-raid alert for ballistic missiles. He entered a camouflaged, net-covered hut, where he turned four keys on switch boxes to trigger Lima's barrage of electronic noise.

Similar setups are dotted around the country, creating a network of invisible signals to stop missiles, guided bombs and drones. When the Night Watch teams are able to retrieve a downed target, they often scour the wreckage to figure out new ways to jam them.

At one research lab, an officer spread out circuit boards and antennas on a table, noting that the latest models were from China.

At the end of 2024, Night Watch discovered that Russian drones and missiles were using Chinese-made components known as Controlled Reception Pattern Antennas, which can detect where jamming signals are beamed from and, in fractions of a second, use complex algorithms to dodge them.

"It was a big problem for us," said an officer known by the call sign Frenchy.

Night Watch and Cascade, the company that makes Lima, worked around the clock for three months to find a solution. The result was Lima Quant, whose own mathematical algorithms work out ways to overcome such an antenna.

But then the Russians doubled the number of antennas from four to eight, then to 16, and now to 32, each time reacting to new Lima updates.

Several Ukrainian and Western air-defense experts who spoke to The Wall Street Journal said a system such as Lima is capable of foiling ballistic missile attacks. And though Russia's success in piercing Kyiv's air defenses with ballistic missiles this year demonstrates that electronic warfare isn't a perfect stand-in for Patriot interceptors, it comes at a fraction of the price and is readily available.

Ukraine uses high-end equipment such as Lima to protect cities and vital infrastructure. Soldiers on the front line face a constant threat of drones that need a cheaper, more abundant antidote.

At a workshop near Ukraine's eastern front, an electronic warfare unit of the Azov Brigade finished work on circuit boards inside a black plastic case, much like those used to store tools. The circuits transmit signals via four antennas on the box for several hundred yards, on frequencies the unit believes Russia is currently using. The devices are distributed across the front line and use the classic jamming method practiced for over a century.

"We make sure that their drone cannot hear its operators," said a sergeant at the workshop.

For front-line soldiers, identifying the frequencies to disrupt is a matter of life or death.

One Azov soldier, who goes by the call sign Dobri, recalled how a Russian drone sped toward him. The weapon dropped to the ground under the signals onslaught unleashed from his vehicle. When he returned to the workshop, he thanked colleagues for the gear that saved his life.

The U.S. is taking notes, said Col. Josh Koslov, the U.S. Air Force's director of non-kinetic operations. "If you are not winning in the spectrum," he said, "you are going to lose the war."