Global vsat forum (“gvf”) Information Paper on
Potential for sharing between IMT and MSS
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Potential for sharing between IMT and MSSOlder L-band satellites (still in use today) use global beams where the footprint of the beam would cover the entire Earth surface as seen from the satellite. More recent satellites use regional beams to cover smaller areas, typically the size of Europe. The most recent L-band satellites use spot beams which cover much smaller areas, of the order of 1,000 km in diameter. There are two main benefits from the use of smaller beams. First, the higher satellite antenna gain improves the link budget on the forward and return links, allowing the use of smaller user terminals. Second, the use of spot beams allows the same frequencies to be used many times on the same satellite. The ability of the MSS systems to share with other services is very limited, partly due to the ubiquitous coverage provided by the MSS and partly due to the high sensitivity to interference (user terminals and satellites have to be sufficiently sensitive to receive the desired signal from 36,000 km; and both the user terminals and satellites are limited in the available power to transmit the desired signal). Most of the ITU frequency allocations to the MSS in L-band are not shared with other services, and the few MHz of spectrum which is allocated to other services has very little use by those services. This reflects the limited scope for frequency sharing. The possible use of wireless microphones in L-band was studied by the European Conference of Postal and Telecommunications Administrations (“CEPT”) between 2008 and 2010, concluding that sharing between those devices and the MSS is not feasible.9 Ultra-wideband (“UWB”) systems are authorised to operate in L-band (and many other bands), but with very stringent limits applying to emissions in L-band.10 6 Galileo is a global navigation satellite system (“GNSS”) currently being built by the European Union (“EU”) and European Space Agency (“ESA”). 7 GPS is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the United States government and is freely accessible to anyone with a GPS receiver. 8 Glonass is an acronym for Globalnaya Navigatsionnaya Sputnikovaya Sistema, or Global Navigation Satellite System. Glonass is a radio-based satellite navigation system operated by the Russian Aerospace Defence Forces. It both complements and provides an alternative to the GPS system. 9 See ECC Report 121 and Report 147 (available at http://www.ecodocdb.dk/). 10 See, for example, European Commission Decision 2009/343/EC (available at http://eur- lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32009D0343:EN:NOT). Recommendation ITU-R M. M.1799 recommends that cellular or similar high-density mobile systems cannot share with MSS uplinks in the band 1,668-1,675 MHz.11 Based on these studies, it is clear that terrestrial IMT systems cannot share with L-band GSO MSS systems, and hence the frequency bands 1,518-1,559 MHz, 1,626.5-1,660.5 MHz and 1,668-1,675 MHz are not suitable for identification for terrestrial IMT. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 2.11 Mb. Share with your friends:
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