Ukraine’s latest defense against Russian missiles: Making them miss

KYIV — As Ukraine rations its limited air defense missiles, it is increasingly betting on the homegrown Lima electronic warfare system to disrupt and redirect Russian drones and missiles.

One of Lima’s developers told POLITICO how it works by interfering with the incoming weapon’s guidance system.

Unlike traditional air defenses, which destroy incoming threats by smashing into them with missiles, Lima jams and spoofs satellite navigation signals, causing Russian weapons to veer off course. The system has become an increasingly important layer of Ukraine’s air defense architecture as Russia intensifies long-range strikes and Kyiv faces persistent shortages of expensive interceptor missiles.

Lima, developed by Cascade Systems, a Ukrainian defense startup registered in the U.S., generates powerful jamming fields that disrupt satellite navigation.

If satellite signals are blocked, Russian long-range weapons can continue flying using inertial navigation systems, but their accuracy can deviate by about 2 kilometers for every 100 kilometers traveled — meaning they are less likely to hit their targets.

“When Lima is on, it makes missile deviation even greater. In addition to simply suppressing navigation, we use spoofing and the substitution of coordinates by several kilometers. We can make their missiles fall in fields instead of hitting their targets,” said Alchemist, a Lima developer and commander of the Night Watch, an electronic warfare unit of the territorial defense forces of Ukraine. He asked to be identified only by his call sign for security reasons.

Lima’s appeal lies partly in its scale and cost. Unlike many other tactical jammers, Lima can cover large swaths of territory, protecting critical infrastructure. Each unit costs up to 3 million hryvnia (€58,000) to produce, depending on the iteration, according to Cascade. The company estimates that it takes 30 to 100 units to protect a major city — around €5 million.

That’s about the cost of a single Patriot PAC-3 missile.

Cascade has already supplied more than 400 Limas. The military began using them in July 2024, and their use was broadened to also defend civilian infrastructure in October 2025.

According to the company, Limas jammed 20,500 Shahed drones and misdirected dozens of ballistic and cruise missiles in the last 18 months.

The latest iterations of Lima can suppress long-range weapons — including ballistic missiles — which rely on systems such as Russia’s GLONASS satellite navigation, said Maksym Skoretskyy, the head of the electronic warfare department of the land forces of Ukraine.

How Lima works

Lima spoofs satellite navigation signals used by Russian missiles and drones, feeding them false coordinates. According to developers, some past attacks were diverted by making the incoming weapons think they are in Peru.

The remains of Russian weapons are pictured in Kharkiv, Ukraine on April 30, 2025. | Ivan Samoilov/AFP via Getty Images

The Lima system can also create a “dead zone” where a Russian drone loses its guidance signal.

“When we … create a wide enough zone, protected by Lima stations, a missile won’t even hit the city. We will send it into an open field,” Alchemist explained.

Glide bombs — a conventional bomb equipped with winglets to give it more range — were harder to counter, as Russia uses them mostly against the frontline areas. It’s more difficult for Ukraine to create signal dead zones there, as it controls only part of those areas. But once engineers found ways to overcome newer Russian anti-jamming antennas, Lima began diverting glide bombs as well.

“Even if the glide bomb deviates from its target for about 20 meters, it already means the target will continue to exist,” said Skoretskyy.

But relying only on electronic warfare also carries risks.

Jammed Russian drones and missiles still fall and hit something, causing damage, Skoretskyy said. Conventional kinetic air defenses, on the other hand, destroy an incoming missile or drone in the air; the resulting debris still hits the ground but causes less damage than an intact redirected weapon.

“However, will Russian ballistic missiles hit the desired target when Lima is on? I would say unlikely,” Skoretskyy added.

Never-ending tech battle

Developers say the first iterations of Lima appeared in 2022 to fight Russian cruise missiles. But it took years of experiments and more than $2 million in their own funds for Cascade Systems to overcome the skepticism of Ukraine’s government and senior army commanders. They began receiving state contracts at the end of last year.

Electronic warfare is a never-ending battle of signals and math. Every time Ukraine develops a stronger system, Russia adapts its weapons and antennas to resist it, including by updating navigation systems to allow drones and missiles to maintain stable satellite connections even under electronic attack.

In early 2025, Russian forces introduced upgraded anti-jamming Kometa antennas that rendered existing Ukrainian electronic warfare systems, including earlier versions of Lima, ineffective.

“That’s when real life started,” Alchemist said. “We were living in our lab, trying to crack the new Russian antennas.”

After three months, engineers developed a new version called Lima Quant, designed specifically to overcome the upgraded Russian defenses by combining traditional spoofing with new high-frequency signals to confuse Kometa.

“We constantly change Lima based on characteristics of Russian weapons, analyze hits, and provide recommendations to the general staff on where to put it and how,” Alchemist said. “War evolves all the time.”