Redondo Beach, California-based TRW Inc, Constellation Communications Inc and Ellipsat Corp have filed a joint proposal to the US Federal Communications Commission for sharing the mobile-satellite service systems’ radio frequency spectrum. The move pits the trio against Motorola Satellite Communications Inc and Loral Qualcomm Satellite Services Inc, which filed a separate joint proposal in early October. The Motorola and the Loral proposals ask the the Commission to assign spectrum to systems as they go live, with the first system authorised to operate across the available 16.5MHz frequency band. Subsequent systems would be allocated a portion of the 16.5MHz band after putting birds in orbit. The TRW Constellation Ellipsat team opposes this methodology, which it dubs the ‘first up gets all available spectrum’ approach. Dividing the frequency band in this way would give incentives to the first mobile satellite service operator to deprive others of access to the spectrum, and would be difficult to implement internationally, says TRW. The TRW Constellation Ellipsat spectrum-sharing proposal calls for interference sharing of the full 16.5MHz band, which goes from 1,610MHz to 1,626.5MHz, as the best way to allocate the spectrum. Each system could than operate across the full spectrum allocation and tolerate interference from other systems. This, they say means all applicants could be licensed, adding that the certainty of spectrum availability for all qualified applicants will improve their ability to obtain funding and to be recognised internationally.
