Sentinel Spectrum: the Case for EO and Space Science Spectrum

Europe’s Investment in Earth Observation (EO) Satellites

Sentinel 1A, the first of Europe’s Sentinel EO satellites, was successfully launched in April 2014. This is the first of a constellation of satellites dedicated to the European Union’s Earth observation program, Copernicus. The global monitoring data provided by the Sentinels will contribute to improving maritime security and the surveillance of the marine environment; the monitoring of climate change; the mapping of forest, water and soil management; and will provide support in emergency and crisis situations. Sentinel-1B, an identical satellite, is scheduled for launch in late 2015.

As an example of Europe’s leading technology, the Sentinel-1 satellites are the result of collaboration between the European Space Agency (ESA), the European Commission, the European space industry and data users. The satellites were designed and built by a consortium of about 60 companies led by Thales Alenia Space and Airbus Defence and Space.

Challenges at WRC-15 

The Sentinel-1 satellites each operate a Synthetic Aperture Radar (SAR) in the 5350 – 5470 MHz band (C-band), which is currently allocated to the Earth-exploration satellite service. Item 1.1 of the agenda of the 2015 International Telecommunication Union (ITU) World Radiocommunication Conference (WRC-15) is a challenge on the horizon if the functionality and implementation of the full range of the Sentinel services and applications is to be preserved. The topic of consideration in item 1.1 is “to consider additional spectrum allocations to the mobile service on a primary basis and identification of additional frequency bands for International Mobile Telecommunications (IMT) and related regulatory provisions, to facilitate the development of terrestrial mobile broadband applications.”

It is thus envisaged that the 5350 – 5470 MHz band will be allocated to mobile services to allow RLAN. Many space industry members are concerned that this will cause harmful interference to the SAR systems (including the Sentinel satellites) operating above land and along coastal areas.

As Daniela Genta, head of radio regulatory affairs and policy at Airbus Defence and Space states, “Sentinel 1 is the first space-based contribution to Copernicus (GMES). Other national missions are already planned. The European Union, for the benefit of the European citizens, have engaged to a level of ambition that industry can deliver with state of the art technology and applications. The access to spectrum resources is embedded in the program and shall not be open for negotiations every WRC”.

Protection of EO and Space Science Spectrum

The commitment of the European Commission and member states to ensure the availability and protection of spectrum for EO is given in Article 8 of Decision No 243/2012/EU of the European Parliament and of the Council of 14 March 2012 establishing a multiannual radio spectrum policy program:

“1. Member States and the Commission shall ensure spectrum availability and protect the radio frequencies necessary for monitoring the Earth’s atmosphere and surface, allowing the development and exploitation of space applications and improving transport systems, in particular for the global civil navigation satellite system established under the Galileo programme(1), for the European Earth monitoring programme (GMES)(2), and for intelligent transport safety and transport management systems.”

The European Commission recently mandated the CEPT to study the potential impact of RLANs, and other wireless devices, in this frequency band and the implications of interference on the functionality of the Copernicus system. These studies will continue until November 2014.

Any mitigation solution or technique to reduce the technical incompatibility between RLAN and EO services will need to be considered carefully; from the perspective of all parties involved. The solution, which might include compliance standards for equipment, will need to be implemented uniformly and strictly by all member states. Any solution also needs to be considered globally. It is understood that the European Commission is already liaising with U.S. bodies in this regard.

Space Spectrum Shake-up 

WRC-15 is expected to lead to a significant shake-up of spectrum allocation for the space community. It would appear that the pressure on allocations is most acute in relation to the C-band, but also the L-band, which sit uncomfortably adjacent to Wi-Fi spectrum bands. A greater sharing of spectrum is inevitable.

The space community is encouraged to work closely together to provide an evidence base as to the space sector’s spectrum requirements, and projections for the next 25 years, to include the economic and social value of such satellite uses of spectrum and the range of services that can be offered now and in the future; the types of customers who can and will benefit from the services and where those customers are or will be based; an estimate of growth areas and markets; an indication of new technologies and implications for services and sharing possibilities; what levels of interference could and could not be tolerated and the implications; and the benefits now and in the future of such services. This evidence base needs to be communicated to the CEPT, national regulators and the European Commission to ensure that the space community’s voice is heard and an efficient balance in spectrum allocation, now and in the future, can be achieved. VS