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

2. 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.

3. 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

4. Non-Planned Ku Band FSS Frequencies
Space-to-Earth Direction
10.95 – GHz
11.45 – GHz
11.70 – GHz (Region 2)
12.20 – GHz (Region 3)
12.50 – GHz (Regions 1 and 3)
Earth-to-Space Direction
14.00 – GHz

5. Non-Planned Ka Band FSS Frequencies
Space-to-Earth Direction
17.30 – GHz (Region 1)
17.70 – GHz
19.70 – GHz
Earth-to-Space Direction
27.50 – GHz
29.50 – GHz

6. 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

7. SATELLITE COVERAGE Uplink Coverage Downlink Coverage
Note: This is an example coverage map; actual coverage varies depending on
actual satellite design.

8. 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

9. 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%

10. 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.

11. 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

12. 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

13. 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%

14. 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