As the Russian war in Ukraine drags on, electronic warfare techniques may be giving Russian forces an edge, according to some intelligence analysts.

In the latest phase of the war, which is now entering a sixth month of combat, various observers have noted that Russian electronic warfare (EW) systems are playing a greater role.

The EW designation refers to a range of hardware and software systems that can jam, intercept, or locate enemy communications. In June, the Associated Press reported that these systems were starting to be used more in eastern Ukraine, where shorter supply lines allowed Russian troops to move the specialized EW equipment closer to the battlefield. Ukrainian officials told AP that GPS jamming of drone guidance systems presented a “pretty severe” threat to their effectiveness.

A new analysis published in Spectrum, a news publication produced by the Institute of Electrical and Electronics Engineers (IEEE), also argues that while EW did not play a decisive role in the invasion, it is now helping to tip the scales in Russia’s favor.

“Experts have long touted Russia as having some of the most experienced and best-equipped EW units in the world,” writes Bryan Clark, director of the Hudson Institute’s Center for Defense Concepts and Technology, for Spectrum. “So in the early days of the 24 February invasion, analysts expected Russian forces to quickly gain control of, and then dominate, the electromagnetic spectrum.

“But after nearly a decade of rehearsals in eastern Ukraine,” Clark continues, “when the latest escalation and invasion began in February, Russian EW was a no-show.”

However, Clark writes, now that Russian troops control more territory in Ukraine and increasingly resort to “siege tactics” around Ukrainian cities, EW is starting to come into play. In one example, Russian troops have reportedly been able to jam the radar communications of Ukrainian drones, preventing them from effectively identifying Russian artillery batteries. Meanwhile, interception techniques allow Russian forces to locate and target Ukrainian artillery, pressing home their significant numerical advantage in terms of firepower.

In addition to jamming measures, unofficial hacking efforts have also played a role in the conflict, including a number of anti-Russian groups operating under the guise of Anonymous.