Early Signals Mixed for WRC-12 Studies for Mobile Satellite Allocations

GENEVA -- Space, weather and other interests raised various concerns with studies of bands for possible allocation to the mobile satellite service at the 2012 World Radiocommunication Conference. The WRC-12 agenda item will be discussed next week in the ITU-R working party on efficient orbit/spectrum utilization for the mobile satellite and radio navigation satellite services.

A report used at WRC-07 indicated a shortfall of 19-90 MHz by 2020 for the satellite component for International Mobile Telecommunications (IMT) in the Earth-to-space direction. IMT is the international spec for voice and data communications. The total shortfall for MSS is larger. Studies of possible bands for new allocations to MSS are focusing on the 4-16 GHz range (CD Sept 16 p13).

Several weather and space intergovernmental agencies said the 7145-7235 MHz, 7750-7900 MHz and 8400-8500 MHz bands should be removed from the list of candidate bands. The European Space Agency, Eumetsat and the World Meteorological Organization said regulation would be needed for unwanted emissions for compatibility with Earth exploration-satellite service (passive) operations above 10.6 GHz.

Germany wants the ITU-R studies to consider the band 15.43-15.63 GHz in the WRC-12 preparatory studies. Studies by the European Conference of Postal and Telecommunications Administrations are looking at its potential as an MSS uplink band. But the band is also being studied for a primary allocation to the radiolocation service under another WRC-12 agenda item.

The U.S. said its studies of sharing between the space research service and MSS systems using medium earth orbit satellites in the 7190-7235 MHz band show that agreed short- term interference criteria for the space research receivers could be exceeded. Some emissions limits probably will be needed to protect space research systems, the U.S. said. More study of the specific values is needed.

Sharing the 7750-7850 MHz band between the meteorological satellite service and the MSS probably wouldn’t work, the U.S. said, because of an expectedly large number of meteorological satellite and MSS terminals and because the location of many meteorological satellite terminals isn’t known.

Many administrations have international fixed service deployments in the 7055-7250 MHz, 7750-7900 MHz, 10.5-10.6 GHz, and 14.8-15.35 GHz bands, said participants in an ITU-R working party dealing with fixed wireless and other systems. The participants think sharing studies should concentrate on other bands.

Qualms were also raised by participants in the ITU-R working party about some mobile and radio-determination services. They said the radio regulations provide for fixed and mobile allocations in the 4400-4990 MHz band in all regions, with other allocations for sub-bands. The WRC-07 added regulatory provisions for use of the 4400-4940 MHz band for aeronautical mobile telemetry for flight testing by aircraft stations, they said, and at least one administration has started to develop the systems.

WRC-07 aeronautical mobile allocations made for the 5150-5250 MHz band are intended for telemetry applications in the air to ground direction, the group said referring to Europe, Africa, former Soviet states, some Arab countries and Brazil. They also said the frequency band 13.25-13.4 GHz is allocated for the aeronautical radio-navigation service on a primary basis, limited to Doppler navigation aids systems.

Nigeria said studies should consider the effect of adjacent band interference on current services, particularly the fixed satellite service. Russia also has concerns with the sharing studies.