The queue started before your programme did
The ITU Radio Regulations establish a strict priority system: the administration that files first, coordinates first, and protects its frequencies first. That principle sounds simple. The consequence is not. A GEO filing submitted today enters a coordination queue that may already contain hundreds of prior networks operating in the same arc and band. Your satellite's right to transmit depends on resolving interference with every one of them that objects.
For non-geostationary (NGSO) systems, the Rules of Procedure introduced after the 2019 World Radiocommunication Conference (WRC-19) added a seven-year bring-into-use milestone and a milestone-based deployment schedule. Miss the first satellite deployment deadline and the filing lapses. The ITU does not grant extensions for launch vehicle delays, regulatory hold-ups in a third country, or programme funding gaps. The clock runs regardless.
API, CR/C and N: what each step actually does
The coordination sequence has three formal stages. The Advance Publication of Information (API) is submitted up to seven years before the satellite's notified date of bringing into use. It places the network in the public record and triggers a four-month window during which other administrations may note potential interference. The API does not confer any rights; it is a reservation of intent, nothing more.
The Coordination Request (CR/C) follows, typically two to three years before launch for a GEO mission. This is the substantive step: the filing must include detailed technical characteristics, the coordination arc, and the interference calculations that demonstrate compatibility with prior-recorded networks. Administrations with potentially affected assignments have four months to request coordination. Each request opens a bilateral negotiation that can last years if the parties disagree. Only after successful coordination, or after the objecting administration fails to respond within prescribed periods, does the filing move to notification.
Notification (N) is the final submission to the ITU's Master International Frequency Register. A recorded notification carries full regulatory protection. An unfavourable finding, issued when coordination is incomplete, means the network is registered but carries no interference protection against prior networks. Operating under an unfavourable finding is legal, but any interference you cause to a prior network is your administration's liability to resolve.
GEO slots: scarcity that does not appear on any spectrum chart
The geostationary arc is a single ring at 35,786 km altitude. Orbital slots are defined by longitude to a precision of 0.1 degrees. The most commercially valuable portions of the arc, particularly those with good coverage of populated regions in C, Ku and Ka bands, are already heavily subscribed. An administration seeking a new GEO slot in a congested position must coordinate with every prior filing that overlaps in frequency and arc separation.
Some administrations hold filed slots as a strategic asset, maintaining minimal satellite presence to preserve the registration while the slot's commercial value appreciates. The ITU's bring-into-use rules and the regulatory milestone framework introduced at WRC-19 were designed partly to address this, but legacy filings pre-dating those rules retain their priority. For a new entrant seeking a prime slot, the realistic path often involves negotiating a coordination agreement with an incumbent, which may include frequency segmentation, power limits, or commercial arrangements outside the ITU process entirely.
Where programmes go wrong
The most common filing mistake is treating spectrum as a procurement item rather than a programme dependency. Administrations that begin the API process after the satellite design is fixed discover that the frequencies their payload was designed for are unavailable, or available only with power constraints that reduce link margin below the mission requirement. Redesigning a payload after PDR is expensive. Redesigning it because of a frequency coordination outcome that could have been identified two years earlier is avoidable.
A second category of error involves the filing administration itself. ITU filings must be submitted by the national administration, meaning the government's designated radiocommunication authority, not the satellite operator or manufacturer directly. Countries that lack an active radiocommunication bureau, or whose bureau has no experience with space filings, often submit incomplete or technically inconsistent documentation. The ITU's Radiocommunication Bureau returns such filings for correction, and each correction cycle costs months. Establishing the administrative relationship and building the technical submission capability inside the national authority is work that must begin before the satellite contract is signed.
Coordination correspondence is conducted in French, English and Spanish. Technical annexes follow ITU-R Recommendation formats that are specific and unforgiving. A value entered in the wrong unit, or a reference frequency omitted from the technical characteristics table, is grounds for a finding of incomplete submission.
Timelines that cannot be compressed
For a GEO mission, the minimum credible timeline from first API submission to a fully recorded notification with coordination complete is five to seven years, assuming no contested coordination. Contested coordination, which is common in crowded bands, extends this. NGSO constellations face comparable timelines for the first filing, plus the ongoing obligation to meet deployment milestones for subsequent tranches.
For a small sovereign mission in a less congested band, say a VHF/UHF LEO satellite using frequencies already coordinated by the national administration for an existing system, the timeline can be shorter. But this is the exception. Planning a national programme around the optimistic case is how programmes arrive at their launch window without a valid frequency assignment.
The practical implication: spectrum work should begin at programme inception, in parallel with mission concept studies, not after a launch contract is signed.
What candour requires us to say
No filing consultant, and no prime contractor, can guarantee a coordination outcome. The ITU process is multilateral and administrative; it involves sovereign administrations acting in their own interest. An administration that objects to your filing and refuses to coordinate is within its rights under the Radio Regulations. The available remedies are negotiation, escalation through the ITU's procedures, and, in extreme cases, dispute resolution mechanisms that are slow and uncertain.
Filing priority is also not the same as operational protection in practice. Interference disputes between administrations are common, and resolution often depends on diplomatic relationships as much as regulatory standing. A well-filed, fully coordinated network operating from a country with limited diplomatic reach may find enforcement of its rights difficult if a larger administration's operator causes interference. This is a real constraint. It does not make filing less important; it makes the quality of the filing and the strength of the coordination record more important, not less.
Engineering parameters
| API submission window | Up to 7 years before notified date of bringing into use (ITU Radio Regulations, Appendix 4) |
| CR/C coordination response period | 4 months for administrations to request coordination after CR/C publication |
| NGSO bring-into-use milestone (post WRC-19) | First satellite must be launched within 7 years of the filing's notified date |
| GEO slot precision | 0.1-degree longitude increments along the geostationary arc |
| Typical GEO coordination timeline (uncontested) | 5 to 7 years from API to recorded notification |
| Typical GEO coordination timeline (contested, congested band) | 7 to 12+ years; no regulatory upper bound on bilateral negotiation duration |
| Filing languages | French, English, Spanish (ITU official languages); technical annexes per ITU-R Recommendation formats |
| Submitting party | National radiocommunication administration only; operators cannot file directly with the ITU |
| Unfavourable finding consequence | Network registered without interference protection against prior-recorded assignments |
| WRC review cycle | Every 3 to 4 years; regulatory framework changes at each conference can affect in-progress filings |
One contract, one accountable engineer
Commissioned as one programme, not a stack of contracts: spacecraft, launch, ground segment, mission control, training and handover are priced together. Source-access terms and audit rights are agreed in writing before signature. Review your filing timeline with us.