Operators offer many of their mobile services in L-Band including mobile telephony, maritime communications, satellite news gathering and aeronautical radio-navigation.
Demand for such services continues to increase, but only 33 MHz of spectrum is available to all mobile satellite operators worldwide. The scarce availability of spectrum makes it difficult to accommodate current and future operator demand.
Because of this challenge, all operators in ITU Regions 1 and 3, which includes Europe, Africa, Middle-East, Asia and Oceania, meet at the end of each year to agree on how to share the L-Band frequencies among them for the following year.
Allocation of the L-Band spectrum is agreed upon following peer review of individual operators requirements. Each operator must define the mutual compatibility of its services with those of all other operators. Once all requirements have been reviewed and compatibility taken into account, an optimised solution is determined, also with the help of sophisticated software tools specifically developed for this purpose.
"Unfortunately physical limits mean that not all requirements can be satisfied,” explains Edoardo Marelli, head of the ESA Frequency Management Office.
“But one way or another we have to reach an agreement on how to assign frequencies for 2013, the alternative being a lawless 'wild-west' situation with continuous communication interruptions due to radio interference between operators. In such a situation, there would be no guarantee of service to customers.”
ESA has a seat at the negotiations table to ensure the mobile satellite payload on its Artemis telecommunications satellite will be allocated enough frequencies to operate. Other participants include: Inmarsat (UK), Thuraya (UAE), JRANSA (Japan), RSCC (Russia), ACeS (Indonesia) and SingTel-Optus (Australia). As users of the Artemis payload, Telespazio (IT) provides support to ESA during the negotiations. Sitting in as an observer this year is the Beijing Global Information Centre for application and exploitation (BGIC). Next year China plans to be a participant in the ORM.
Negotiations are likely to include the mobile satellite payload on Alphasat I-XL, set to launch in 2013. Alphasat I-XL , being developed through a public-private partnership between ESA and Inmarsat, will be integrated into the Inmarsat satellite fleet to provide mobile satellite communications services for users in the maritime, land and aviation sectors. It will provide coverage over Europe, Asia, Africa and Middle East.
Alphasat I-XL uses Alphabus, the new European high-power telecommunications platform jointly developed by Astrium and Thales Alenia Space under a joint ESA and CNES contract.
For more information, see the link in the column to the right.
