A satellite cannot simply switch on its transmitter once it reaches orbit. Radio frequencies and orbital positions are shared resources, and their use is coordinated internationally through the International Telecommunication Union (ITU) and licensed by national authorities. For new operators, spectrum is often the longest lead item in the entire project.
The role of the ITU
The ITU Radiocommunication Sector maintains the Radio Regulations, an international treaty that allocates frequency bands to services such as fixed satellite, Earth exploration or amateur satellite. It also keeps the Master International Frequency Register, in which satellite networks are recorded once coordination is complete.
Filings go through national administrations
Operators do not file with the ITU directly. The filing is submitted by a national administration, usually the telecommunications regulator of the country responsible for the satellite. The typical sequence is:
- Advance publication or coordination request: the planned network, its frequencies and its orbit are published so that other administrations can assess possible interference.
- Coordination: the operator and its administration negotiate with the operators of existing and earlier filed systems.
- Notification and recording: once coordination is complete, the assignments are notified and entered into the register, which gives them international recognition.
- Bringing into use: the frequencies must actually be used within regulatory deadlines, otherwise the filing can lapse.
National licences
In addition to the ITU process, operators usually need a national licence to operate the space station and licences for their ground stations in each country where they receive or transmit. Some countries also require a separate authorisation for the space activity itself.
Practical advice
- Start the spectrum work at the same time as the satellite design, not after the launch contract.
- Choose frequency bands that match the service and that ground station providers already support.
- Keep launch dates and bringing into use deadlines aligned, because a launch delay can put a filing at risk.
Related reading
- Ground Stations Explained: How Satellite Data Gets Back to Earth
- The Outer Space Treaty: The Legal Foundation of Spaceflight
- Satellite Ground Systems: Ground Stations, Antennas and Network Infrastructure
Sources
Cover image: A new antenna for NASA's Deep Space Network. Credit: NASA/JPL-Caltech (PIA24163), public domain.