FIXED SATELLITE SERVICE and UAS (22 September 2010) ACP WGF23/IP26 Abdolmajid Khalilzadeh

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.

ADJACENT SATELLITE INTERFERNCE ES1 ES2 ES3 1 2 3 4 A C B D SAT 1 SAT 2 SAT 3 UA E F G H 2º±0.05º I J 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