Russia is equipping its drones with larger, jam resistant antennas that make Ukrainian electronic countermeasures less effective at disrupting navigation signals, according to Ukrainian officials. The upgrades are forcing Ukraine to adapt its electronic warfare defenses as Russian systems become increasingly resistant to interference.

At the center of the effort are Russia’s Kometa navigation modules, which are produced by VNIIR-Progress. The modules use arrays of small receiving elements called patch antennas to maintain satellite navigation when jamming equipment attempts to block or scramble the signal.

Kometa modules have been recovered from a broad selection of Russian weapons. Ukraine’s military intelligence agency, HUR, lists them aboard Geran drones, glide bomb kits, Iskander-M and Kinzhal missiles, and the new Filin cruise missile in its database of Russian weapons.

The Kremlin is already fielding Kometa modules equipped with 16 element antenna arrays at scale, HUR said Oct. 19. Russia is also establishing serial production of 20 element arrays that can better identify the direction from which jamming originates and compensate for that interference.

Even larger configurations are reaching the battlefield. Serhii “Flash” Beskrestnov, an electronic warfare specialist and adviser to Ukrainian President Volodymyr Zelenskyy on defense technology, said Shaheds carrying antennas with 32 elements have already been found during attacks against Kyiv.

“The more elements, the more electronic-warfare signal sources the antenna can suppress,” Beskrestnov wrote in an October post on Telegram. His assessment points to a difficult contest in which additional receiving elements can make each Russian drone more resilient against Ukrainian jamming systems.

“This race is difficult for us because it is easier for the enemy to increase the number of elements on an antenna than it is for us to add electronic warfare sites,” Beskrestnov said. Russia can expand an antenna array on individual weapons while Ukraine must deploy additional electronic warfare equipment across the areas it is trying to protect.

The consequences reach beyond electronic warfare. Better protected Russian drones can penetrate Ukraine’s EW shield, one of the country’s most affordable and widespread air defense layers, leaving more aircraft to be engaged by comparatively expensive interceptor drones, jets and missiles.

HUR said a Kometa module’s jamming resistance depends on several factors, including the number and arrangement of patch antennas across the array. Performance also depends on the algorithm used by the module’s processing chip to distinguish legitimate satellite signals from electronic interference.

The upgraded antennas are not invulnerable, according to defense leaders. Ukrainian forces can still counter drones carrying them by jamming additional satellite bands simultaneously or by connecting devices in networks that provide the drones with false coordinates.

The commander of Ukraine’s Night Watch unit, who uses the call sign Alkhimik, acquired a 32 element antenna recovered from a crashed Shahed and sold on the secondary market. He told Militarnyi in July that the device was made from two 16 element arrays designed to cover different satellite navigation bands.

The design gave Alkhimik an idea for defeating the upgraded system. “By creating two systems — one operating in the L1 band and the other covering L2/L5 — we’ll be able to jam this antenna without any problems,” he said.

Spoofing offers another countermeasure, according to Fly Group Ukraine. Anatoliy Khrapchynskyi, the defense company’s director of development, told Reuters in September that the method links multiple devices into a network and sends false coordinates to an approaching drone.

“The drone continues to think it is flying toward its target, but its own autopilot, relying on the false coordinates, gradually changes course on its own and steers the craft away from cities into safe areas,” Khrapchynskyi said. The method manipulates the drone’s navigation rather than merely attempting to block it.

Demand for Kometa technology remains substantial. Russian defense firms have ordered more than 100,000 modules in various configurations this year for use in cruise missiles, ballistic missiles, strike drones and guided bombs, according to HUR.