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ACP WGF23/IP26 Abdolmajid Khalilzadeh. FIXED SATELLITE SERVICE and UAS (22 September 2010). COMMERCIAL SATELLITES. The FSS may be able to fulfill the UAS spectrum requirements without the need for a new AMS(R)S allocation
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ACP WGF23/IP26 Abdolmajid Khalilzadeh FIXED SATELLITE SERVICE andUAS(22 September 2010)
COMMERCIAL SATELLITES • The FSS may be able to fulfill the UAS spectrum requirements without the need for a new AMS(R)S allocation • Existing commercial FSS systems at Ku and Ka-band offer immediate access to spectrum for UAS • ITU-R studies have shown that the commercial Ku/Ka bands can support UAS control links and meet the desired UAS link availability.
UAS OPERATING UNDER FSS • Requires modification of ITU Radio Regulations to permit UAS to communicate with a FSS satellite • Requires a WRC Resolution that contains the UAS technical and regulatory requirements • The performance, responsibilities and liabilities of the FSS and UAS operators would be specified in a commercial contract • UAS would not be operating under the AMS(R)S service allocation, but rather as an FSS application
Non-Planned Ku Band FSS Frequencies • Space-to-Earth Direction 10.95 – 11.20 GHz 11.45 – 11.70 GHz 11.70 – 12.20 GHz (Region 2) 12.20 – 12.50 GHz (Region 3) 12.50 – 12.75 GHz (Regions 1 and 3) • Earth-to-Space Direction 14.00 – 14.50 GHz
Non-Planned Ka Band FSS Frequencies • Space-to-Earth Direction 17.30 – 17.70 GHz (Region 1) 17.70 – 18.80 GHz 19.70 – 21.20 GHz • Earth-to-Space Direction 27.50 – 28.60 GHz 29.50 – 31.00 GHz
SATELLITE CHARACTERISTICS • Long lifetime (≥ 15 years) • Low satellite and transponder failure rates • High EIRP and G/T levels over large geographic areas • Well suited for links that utilize small transmit/receive antennas • High radio link availability • Connectivity over large geographic areas, which terrestrial links cannot provide • Multiple transponders are available on each satellite, e.g. 24 Ku-band 36 MHz transponders • Bandwidths typically range from 24 to 120 MHz – the most common bandwidth being 36 MHz
SATELLITE COVERAGE Uplink Coverage Downlink Coverage Note: This is an example coverage map; actual coverage varies depending on actual satellite design.
COMMERCIAL SATELLITE CAPACITY • TRANSPONDER LEASING • Customer can lease all or portion of a transponder • Transponder can be leased on a non-premptible basis • Carrier cannot be moved to restore another carrier • BACK-UP CAPACITY • Due to large number of satellites and transponders, back-up (bandwidth) capacity can be provided. • Back-up capacity available on the same satellite • Back-up capacity available on another satellite
LINK DEGRADATION • A satellite link can be degraded by two primary sources • Atmospheric effects • Adjacent satellite interference • Typical commercial satellite link availabilities range from 99.50% to 99.96%
ADJACENT SATELLITE INTERFERNCE • A satellite link is subject to interference from the transmissions of other co-frequency satellite networks • Interference can occur in the Earth-to-space direction or in the space-to-Earth direction. • Adjacent satellite interference are managed through ITU coordination.
SAT 1 SAT 2 SAT 3 2º±0.05º 2º±0.05º J I 1 2 C G D A B E F UA 4 3 H ES1 ES2 ES3 ADJACENT SATELLITE INTERFERNCE Note: 2º orbital separation is typical of the separation between adjacent satellites
COORDINATION • Satellite operators coordinate the maximum power and EIRP density level of their transmissions, the off-axis gain characteristics of their antennas and the placement of any high power density carriers, e.g. TV/FM • A known and stable interference environment • Links are designed to withstand the expected interference • Internationally, coordination agreements are contained in a formal document that is approved by the involved satellite operators and their respective administrations • Domestically, a formal agreement may or may not be required – depends on the regulations of each administration
ATMOSPHERIC DEGRADATION • Rain is the primary atmospheric source of link degradation at Ku and Ka-band frequencies • The effects of rain can be overcome in various ways • Increasing carrier power level • Changing the carrier modulation & FEC scheme • Increasing the transmitting and/or receiving antenna size • Typical commercial Ku-band link availabilities range from 99.50% to 99.96%
UAS REDUNDANCY • At some point in time, links will degrade or drop-out for various reasons • UAS systems need to incorporate hardware redundancy • UAS systems need to incorporate spectrum redundancy • Capacity • Frequency