Satellite Spectrum Safeguards Urged
GENEVA, Switzerland – Major inter-governmental and private-sector organizations responsible for providing safety-of-life communications to millions of people have requested the national administrations of every region to preserve satellite spectrum for use in delivering mission-critical satellite services worldwide.
The unprecedented demonstration of support for satellite spectrum was made during a series of briefings held at the International Telecommunication Union’s (ITU’s) World Radiocommunication Conference (WRC), where the wireless industry is attempting to get access to satellite spectrum despite reports that previous efforts have already disrupted communications services with serious interference.
Included among those calling for safeguarding of satellite services were the United Nations World Food Program and Office for Coordination of Humanitarian Affairs, the International Civil Aviation Organization, the World Meteorological Organization, the World Broadcasting Unions, NetHope, the International Maritime Organization, and the Space Frequency Coordination Group, a group of space agencies from throughout the world.
In a joint statement issued by an international coalition of seven non-profit associations representing the global satellite communications sector, the show of support was strongly commended: “The high level of support from these organizations makes clear the importance of satellite communications in C band spectrum and how further disruption of safety-of-life services due to wireless interference is unacceptable.”
As governments consider whether any portion of the 3400-4200 MHz band (“C band”) should be identified for IMT, they have heard from the safety-of-life organizations during a series of briefings held for the inter-governmental groups of each major world region, including the Arab Spectrum Managers Group (ASMG), Asia Pacific Telecommunity (APT), the Conference Europeenne de Postes et Telecommunications (CEPT), the Inter-American Telecommunication Commission (CITEL), and the RCC & Commonwealth of Independent States.
“Some administrations may be under a misimpression,” the coalition statement continued. “It is not necessary to support IMT identification if they have already authorized WiMax or other terrestrial wireless services. An identification for IMT is not required to make WiMax or other authorizations comply retroactively with ITU rules. No ITU rule change is required at the WRC in order to enable national deployments of WiMax or other wireless services.”
1. Realistic solutions to protect existing satellite links in C band have not been identified; migration of IMT services to this band would cause more extreme harm to the global community that relies heavily on satellite services.
It is clear from the most recent reports and studies from the ITU that mitigation techniques, such as separation distance, earth station shielding, or the use of filters on satellite receive antennas, to block interference from IMT networks into satellite networks are often ineffective and moreover would be far too severe to be justifiable from a technical or economic perspective. This means that in practice, mitigation measures would not be effectively implemented. Furthermore current IMT proposals offer no protection for FSS receive-only earth stations, which are deployed broadly and on a licence-exempt basis in many countries.
Within the last few months, satellite stakeholders have experienced further degradation of services in some parts of the world due to terrestrial mobile operations using the same C band frequencies. For example, millions of Philippine citizens’ television signals were disrupted due to interference from mobile services. Similar cases of interrupted service were also reported in South Asia, South America, the Caribbean, and Africa. These are not isolated incidents - disruption of C-band satellite services from terrestrial wireless interference has been taking place around the world since 2006.
It is understood that this has been the result of Broadband Wireless Access (BWA) systems being deployed in the C band. However, the negative effects will be far more wide-reaching in the case of terrestrial mobile IMT broadband services, which have larger coverage requirements and are expected to transmit at higher rates and consequently with more power.
2. Global and national studies indicate that less than 50% of the spectrum currently allocated to IMT is in use.
Claims have been made that mobile broadband will need between 1100 and 1900 MHz more spectrum by 2020, even though IMT is not using most spectrum currently assigned for its use. In anticipation of the growth of the mobile industry, the ITU has already allocated and/or recommended a substantial amount of spectrum for use by IMT. Around the world less than 50% of this spectrum is licensed and even less is in use according to a recent detailed study on the subject by LS Telcom.
It would be unwise to unnecessarily reassign spectrum used for other often-critical services. IMT can achieve its growth targets without a need for the additional spectrum they are requesting, often on the basis of predictions, population density and traffic numbers that are grossly exaggerated.
New and existing C band satellite services are actually bridging the digital divide. It is the duty of the international community to safeguard these vital services. The effects of failing to do so fall disproportionately on the developing world and rural areas. IMT should be directed to use their current frequency allocations fully and more effectively, or concentrate its planning for additional allocations to other, more appropriate bands.