North Korea earlier this year jammed military communications running through a South Korea satellite, according to a report in the Joong Ang Ilbo.

The newspaper, which quoted an anonymous South Korean military official, said a powerful signal sent from a location near Pyongyang caused interference to military communications on the Koreasat 5 satellite in March this year.

However, as usual with such leaks from the Korean government to the local media, what actually happened remains far from clear.

Koreasat 5 was launched in 2006 and carries a mixed commercial and military payload.

On the commercial side are 24 ku-band transponders operated by Korea Telecom that carry Korean TV channels and a direct-to-home service called Dream TV that’s aimed at The Philippines. There have been no reports that these were disrupted.

Fewer details are known about the military side of the satellite, beyond its payload of 8 transponders operating in the “SHF” band and 4 transponders in the ka-band.

SHF describes a very wide range of frequencies and that makes it more difficult to determine a possible application. But a good guess is probably a network that links individual soldiers together and to a headquarters location.

Satellite jamming, like radio jamming, isn’t as difficult as you might think. It typically involves sending a strong signal towards the satellite that disrupts the legitimate signal. The difficulty comes in getting enough power into the sky, and that usually requires commercial grade communications gear and a large dish.

As we’ve written before, there are plenty of large satellite dishes near Pyongyang. Here’s one example.

But, satellite jamming remains a fairly unusual action.

The most active nation on the satellite jamming front at present appears to be Iran. International television and radio broadcasts from both the BBC and Voice of America have been disrupted across Europe and the Middle East for months and Iran has been blamed.

As of time of writing, the story on North Korean jamming doesn’t appear to have made it into English on the Joong Ang website. There is a version on Daily NK.