Effective space plans for satellite connectivity and broadcasting

Pier Francesco Foggia, Senior Engineer, Access to Spectrum and Orbit Resources, and Zeljko Mendas, Senior Engineer, Planned Spectrum, Eutelsat

In 1977, the World Administrative Radiocommunication Conference adopted a new global plan to secure equitable orbital access for satellite broadcasting for each Member State of the International Telecommunication Union (ITU).

Appendices 30 and 30A — Direct-to-home services

This led to the addition of Appendices 30 and 30A in the Radio Regulations, the international treaty that governs the use of the frequency spectrum and associated satellite orbits.

Each ITU Member State was assigned 10 channels with a bandwidth of 27 megahertz (MHz) to be used for direct-to-home broadcasting services with domestic coverage.

However, the original Broadcasting Satellite Service (BSS) Plan established at the 1977 conference covered only countries in ITU Regions 1 and 3 (see map), leaving out the Americas and parts of the Pacific.

The Regional Administrative Radiocommunication Conference in 1983, however, added national frequency assignments for Region 2 countries, thus completing the global plan.

Digital in the 1990s

The situation changed dramatically in the 1990s with the emergence of digital modulation and digital broadcasting. Improved technical characteristics provided more capacity for each country, while the use of smaller receiving antennas and lower operating EIRP (effective isotropic radiated power) levels paved the way for the effective deployment of nationwide satellite-broadcasting services in many countries.

As a result, the World Radiocommunication Conference in 2000 revised the global BSS Plan, adopting new technical parameters. These included more resilient digital modulation and coding, associated with smaller receiving antennas and lower operating EIRP for national coverage.

With these changes, new satellite projects proved technically and economically viable with the creation of sub-regional systems. These new satellite networks covered large territories and provided services to a very large number of countries.

Several of these enjoyed great success, with wide acceptance by the populations they served. This was particularly true in Europe, with the Eutelsat 13E project providing a good example.

Several other projects followed, some national and some supra-national and sub-regional, demonstrating the benefits of the digital broadcasting service for those countries covered by satellite beams, both within and outside Europe.

Renewed national frequency assignments

The last World Radiocommunication Conference, WRC‑19, adopted Resolution 559, providing more than 50 countries with the possibility of applying for a renewed national assignment in the global BSS Plan at an alternative orbital position.

This would enhance signal quality in their territories, enabling those countries to finalize and pursue their own satellite broadcasting plans.

Appendix 30B — planned FSS bands

WARC Orb-88 — The World Administrative Radio Conference on the use of the geostationary-satellite orbit and planning of space services utilizing (2nd session), held in Geneva, Switzerland in 1988 — added Appendix 30B, defining planned fixed-satellite service (FSS) bands, to the Radio Regulations. The new appendix introduced national allotments, guaranteeing equitable access to orbits for every ITU Member State.

Appendix 30B gives each country the right to operate portions of a frequency band, according to specified characteristics, in both C and Ku frequency bands.

The main difference between the traditional, unplanned FSS frequency bands and the Appendix 30B bands is the coexistence of national allocations and additional systems. Since 1988, many changes have been made to fully protect national allotments and allow additional systems to operate in an interference-free environment.

Appendix 30B — increased capacity for satellite communications

The total amount of spectrum allocated to Appendix 30B in the Radio Regulations is 800 megahertz (MHz), including 300 MHz for the C band and 500 MHz for the Ku band. This represents a considerable increase in capacity for satellite communications.

The need for additional resources

The number of satellites capable of operating in the planned bands has increased significantly over the last 30 years, reflecting interest among satellite operators and in turn increasing the need for spectrum resources.

In addition, many countries have been able to convert their national allocations into actual frequency assignments, allowing them to operate geostationary-satellite orbit (GSO) satellites in compliance with the Radio Regulations.

The upcoming World Radiocommunication Conference (WRC‑23) will address several proposed amendments to Appendices 30, 30A and 30B.

The proposed modifications under WRC‑23 agenda item 7 follow on from the latest study cycle — aiming to ensure equitable access to space for each country and make resources available for satellite space stations.

These bands, as the only ones available for national satellite projects, are especially crucial for emerging economies.

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Header image credit: Eutelsat