To the Moon and back for finite frequencies

For decades, the European Space Agency (ESA) has served as permanent executive secretary of the Space Frequency Coordination Group (SFCG), a little-known technical body charged with coordinating and managing the radio waves used for communication by all space-faring organisations.

The SFCG has worked to ensure that radio frequencies are wisely and fairly used for many years - work that is far more important than the committee’s arcane technical name would suggest.

“There is only a finite range of radio frequencies that can be used by spacecraft and satellites to communicate between each other and back to ground stations on Earth,” said Edoardo Marelli, head of ESA’s Frequency Management Office.

“The role of the SFCG is to coordinate the frequencies allocated to civil spaceflight use and to optimise the benefits of this precious and very limited natural resource.”

The SFCG’s 29 regular members include NASA, ESA, national European space agencies, Eumetsat, NOAA, and national agencies from Russia, China and 14 other nations.

Institutional observer members include the International Telecommunication Union and the World Meteorological Organisation.

“SFCG was started by ESA and the French space agency 32 years ago, and it’s one of the most mature and longest-running examples of international cooperation in space,” said Enrico Vassallo, responsible for frequency coordination at ESA’s ESOC Establishment.

“It’s up to ESA to set the agenda, manage issues and, when necessary, break ties to ensure that the annual meetings produce decisions and results that enable all operators to build and fly their missions.”

2012’s seven-day meeting was hosted by ESA at ESOC in Darmstadt, Germany, and ended on 20 June. Delegates agreed on a number of important issues, including coordinating radio frequencies for ESA’s Solar Orbiter mission, planned for launch in 2017, and identifying the bands to be used for future exploration missions around, or on, the Moon.

By cooperating in the SFCG, all space agencies gain the benefits of reducing the risk of interference to their missions, protecting the frequency bands allocated to space services from other spectrum users and creating strong opportunities for cross-support and interoperability.

“And that boosts return on space investment for everyone,” said Vassallo.

Manfred Warhaut, head of mission operations at ESA, explained that access to space is not only a matter of developing launchers.

“It also requires well-managed radio frequencies for communication. Without that, no one would fly any missions at all.”