Space clutter jams radio signals

Government leaders obsess about the possibility of cyber warfare and electronic warfare moving into space and potentially jamming or threatening the military’s vital communications, navigation and imaging assets in orbit. But commercial satellite operators contend that the biggest issue they face isn’t deliberate jamming or hacking attacks, it is unintentional radio interference from other spacecraft and ground stations.

Radio frequency interference in space has been growing, Stewart Sanders, chairman and director of the Space Data Association (SDA), said March 13 during a panel on orbital radio frequency interference issues at the Satellite 2012 conference in Washington. There are a number of reasons for this, and most are not related to intentional jamming, he said. Where it used to take highly advanced nations with highly trained personnel to launch and maintain satellites, technological developments have lowered the entry requirements for space, which has increased the number of players in orbit, he said.

Even in cases of deliberate jamming, such as recent attempts to jam Eutelsat transmissions, this only represented about five percent of all detected interference, he said. From a commercial perspective, the vast majority of interference with satellite communications is created by human error, mostly from misaligned antennas and transmitters.

Space situational awareness is just as important for commercial spacecraft as it is for military ones, Sanders said. Satellites need to be aware of what is happening in the local radio frequency spectrum. One of the SDA’s goals is to create an automated system that will manage the monitoring of radio frequency spectrum in space and to develop machine-to-machine communications techniques to share data and warnings about interference issues, he said.

Radio frequency interference also remains a big problem for the military, said Bill Janosky, director of information assurance at Harris CapRock. Information sharing is critical to resolving these issues. One challenge is keeping the personnel who run military communications systems trained and updated on the latest developments, he said. This is especially important when many of them are deployed in remote areas. The Defense Information Systems Agency is trying to sort out this issue through additional training and awareness of interference issues in satellite communications.

Another area of concern is security. Information assurance standards are necessary to minimize operational risks, Janosky said. To ensure information assurance in satellite communications, commercial and government operators need to focus on three areas: confidentiality, availability and integrity. A review process would also help to identify, mitigate and manage risks for satellite communications operators, he said.

The bulk of radio frequency interference in space is due to the volume of spacecraft operating there, said Bob Potter, president of SAT Corporation. From a cybersecurity perspective, any radio transmitter is a potential target, he said. “Any RF link, no matter what it is, can be compromised,” he said.

Because unique signals and waveforms stand out to anyone trying to intercept or analyze them, the challenge for the DOD is to develop signals that can hide in the crowdby resembling standard transmissions, Potter said.