EUROCONTROL
‘One Sky for Europe’
Most Probable Satellite Communications
Operating Concept for ECAC and other
regions of the world
Presented by Philippe Renaud
Prepared by Phil Platt
ICAO AMCP WG-C
27-30 May 2002
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
European Civil Aviation Conference
EUROCONTROL
(ECAC) Member States
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Communications Problems
EUROCONTROL
‘One Sky for Europe’
• In certain parts of the world (e.g. Europe) air traffic growth
will outstrip communication resource in the VHF band.
• New technologies are being considered in the timeframe of
2010-2015 to complement VHF systems
• Satellite communications could be a possibility but only
with improved performance over current AMSS
• A lower cost satellite communication system would benefit
many other areas of the world too
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Predicted Traffic growth in Europe
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‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Worldwide air traffic
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‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Inmarsat Global beams
EUROCONTROL
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
MTSAT - Japan
EUROCONTROL
‘One Sky for Europe’
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European spot beam
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‘One Sky for Europe’
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Limitation of current AMSS
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‘One Sky for Europe’
• Designed to meet full range of users leading to more
complex system design
• Shared use of spectrum between safety and non-safety
services
• Cost of aircraft installation and avionics
• Large GESs leading limited options for communications
service provision
• Quality of communication service - transfer delays
• Communication costs
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
A new satellite system ?
EUROCONTROL
‘One Sky for Europe’
• Oh no not more technology !
• Haven’t we got enough satellite communications systems
e.g.
 Inmarsat Aero systems H, H+, I, L, C, Mini-Aero, Swift64
 MTSAT (Japan)
 Boeing Connexion
 Iridium
 Globalstar
 ……….
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Safety related communications
EUROCONTROL
‘One Sky for Europe’
• Yes there are many satellite technologies around but they
are designed to support shared use
• Some support AAC, APC - some may support AOC and
ATSC (e.g. Aero H)
• No system supports only AMS(R)S
• Previous experience has shown that reliance on a shared
business case can cause problems
• Where safety and regularity of flight communications are
to be carried by a communications system specific
measures must be put in place to safeguard them
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Requirements
EUROCONTROL
‘One Sky for Europe’
• High levels of availability, reliability and continuity
required for safety and regularity of flight communication
• ATS
 Voice
 Data
• AOC
 Voice
 Data
• Ranked on priority basis
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
ATSC Voice
EUROCONTROL
‘One Sky for Europe’
• ATSC voice is main form for executive control today
• There will be increased use of data link in the future but
voice will be required at least in the foreseeable future
• ATSC use of data link requires new investment in ATS
system on ground - voice is already there.
• VHF RT is the main means of communications in higher
density airspace where there is a ground infrastructure
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
ATS Data Link Services
EUROCONTROL
‘One Sky for Europe’
 ATC Communications
Management Service (ACM)
 Dynamic Route Availability
Service (DYNAV)
 Departure Clearance
Service (DCL)
 Data Link Operational
Terminal Information
Service (D-OTIS)
 ATC Clearances and
Information Service (ACL)
 Controller Access
Parameters Service (CAP)
 Data Link Runway Visual
Range (D-RVR)
 Data Link Logon (DLL)
 Downstream Clearances
Service (DSC)
 Common Trajectory Coordination (COTRAC)
 Pilot Preferences Downlink
Service (PPD)
 Data Link SIGMET Service
(D-SIGMET)
 Flight Plan Consistency
Service (FLIPCY)
 System Access Parameters
Service (SAP)
 Dynamic Route Availability
Service (DYNAV)
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
AOC Applications
EUROCONTROL
‘One Sky for Europe’
• Voice
 assumed to be continued to be required although expected to
decline
• Data Link
 Flight Operations - a few examples of safety and regularity of
flight applications
– Access to Flight Information services (Weather, NOTAM…)
– Weight & Balance
– Performance Data
 Maintenance
– Aircraft condition monitoring
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
New Satellite System (1/2)
EUROCONTROL
‘One Sky for Europe’
• Desirable Features
• Those identified in NGSS SARPs including
 Tailored requirements - safety and regularity traffic only i.e.
priority 1 to 6 in Article 44
– dedicated AMS(R)S spectrum
 Replicate and improve on existing systems
– Voice - VHF RT like with party-line and quick access
– Data - point-to-point and broadcast
 Optimised channels
– tailored to meet the AMS(R)S requirement only until at least
2020 and possibly longer
 Designed to provide required level of performance
– use redundancy in critical communications path
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
New Satellite System (2/2)
EUROCONTROL
‘One Sky for Europe’
• Desirable Features
 Ground Earth Station
– able to reuse existing AMSS infrastructure wherever possible
– allows possibility to use GESs with smaller antennas
– greater flexiblity in deployment e.g. at ATCC or airline sites
 Aircraft Earth Station
– smaller due to limited design goal
– low power, cheaper
 Spectrum Efficiency
– maximise frequency reuse
– specific protocol to carry short frequent data
– efficient mapping of user data to satellite physical link
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Satellite Data Link System
EUROCONTROL
‘One Sky for Europe’
• SDLS is attempting to meet the desirable features
 a tool-box of good ideas
 can pick any or all of the tools to for a new system
• ESA has sponsored a considerable amount of design effort
to match technology with perceived requirements
 a lot of work by satellite system manufacturers
 contribution to the input to a possible open standard for aviation
use
• Development of a ‘ demonstrator ’ underway
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Key features of SDLS (1/2)
EUROCONTROL
‘One Sky for Europe’
• Multiple Access Scheme
 Synchronous CDMA in the fixed to mobile direction
 Quasi Synchronous CDMA in the mobile to fixed direction
• Aircraft Earth Stations
 New CDMA modems being developed
 Low cost solutions
•
Space Segment
 MSS geostationary satellites at L-Band have already been
deployed worldwide and hence are fundemental building block
•
Ground Earth Stations
 Ku or C-Band depending on satellite feeder links
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Key features of SDLS (2/2)
EUROCONTROL
‘One Sky for Europe’
•
Services
 Voice service (point to point and “Party Line”)
 Data service including broadcast and polled
•
Network Architecture
 Capability for decentralised satellite access
•
Satellite Diversity
 Asumed to be required to meet availability requirements
•
Equipment Redundancy
 For both airborne and ground is part of the design
•
Communication Resource Management
 Fixed and demand assignment, handling of priority levels
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Ground Earth Stations
EUROCONTROL
‘One Sky for Europe’
• Two main types of feeder links
 C-band
– currently used by Inmarsat GESs on global and spot beams.
Requires large antennas but the infrastructure is there and will
be for the foreseeable future to support maritime services
 Ku-band
– allows the use of smaller (cheaper) GESs. Could be deployed
at or near ATC centres or airline operational control centre
 Ku-band is more subject to atmospheric disturbance than C-band has to be taken into account in design
 Only Ku-Band VSATs practically allow highly decentralised
access
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
CDMA channel structure
EUROCONTROL
CDMA code
‘One Sky for Europe’
Channel n
Channel n
Channel n
Channel 2
Channel 2
Channel 2
Channel 1
Channel 1
Channel 1
1 MHz Subband
1 MHz Subband
1 MHz Subband
Frequency
Up to 255 CDMA channels per subband
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Satellite Protocols
EUROCONTROL
‘One Sky for Europe’
• Reuse features of AMSS e.g.
 Reliable Link- type service
 AMSS strategy for priority, reference number…
• Data rate determined by type of satellite beam size
• Minimum data rate in global beam
 Basic channel rate is 6.8kbps - in global beam (determined by
vocoder)
 Short message data throughput is 1.35kbps
 Long message data throughput is 2.4kbps
• Spot beams increases rate at least 4 times.
• Broadcast capability - ground to air
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Voice service
EUROCONTROL
‘One Sky for Europe’
• Vocoder rate of 4.8kbps - may be the same as AMSS
• Full duplex circuit mode service for ‘normal’ use
 suitable for AOC and some ATS applications
• Special feature to emulate ATS RT
 ‘party-line’ feature - allows rebroadcast of messages to other
aircraft
 requires dedicated channel per sector
 synchronous CDMA - no signal acquisition time
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Satellite diversity
EUROCONTROL
‘One Sky for Europe’
• Satellite diversity could be required due to  shielding of the aircraft antenna by the structure of the aircraft
 failure of the satellite system
• This requires on the ground  one antenna for each satellite in view by the GES,
 one spare GES antenna to ensure the reliability
• Pre-assigned spectrum for each satellites
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Satellite diversity
EUROCONTROL
‘One Sky for Europe’
Satellite 1
Frame 1
to AES 1
Frame 2
to AES 2
Satellite 2
Frame 1
to AES 1
Frame 2
to AES 2
AES 1
antenna
nom.
antenna
red.
Ground network
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Aircraft Earth Stations
EUROCONTROL
‘One Sky for Europe’
• Simple and cheap
 isotropic antenna
 low RF power - no forced air cooling requirements
 single transmit channel per AES
 need 2 AESs per aircraft to achieve redundancy requirements
 Direct data inputs for Polling Services e.g. A429
 Interfaces to CMU/ATSU and voice distribution system
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Aircraft Installation
EUROCONTROL
‘One Sky for Europe’
Other Data
Links
CMU
(ATN Router
or ACARS)
Positional and
other ADAP
information
Satellite Data
Unit
Onmidirectional
Antenna
Power
Amplifier/LNA
SDLS voice
channel
selection unit
Positional and
other ADAP
information
Audio
Distribution
System
Satellite Data
Unit
Power
Amplifier/LNA
Audio from other
systems e.g.
VHF, HF, etc
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Initial Deployment in ECAC
EUROCONTROL
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Ground architecture
EUROCONTROL
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Other deployment options
EUROCONTROL
‘One Sky for Europe’
• Whilst a solution based on global beams is a practical early
solution (maybe preferred in ECAC area), other options
are possible
• Incremental flexible deployment can be provided through
the use of spot beams where required
• This could be an attractive first step in some areas of the
world e.g. where there is not a well developed terrestrial
infrastructure
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Later deployment in ECAC
EUROCONTROL
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Ground Architecture
EUROCONTROL
‘One Sky for Europe’
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
SDLS Demonstration Programme EUROCONTROL
‘One Sky for Europe’
• SDLS Programme Phases
 Key system performance demonstrator with AESs on ground (ongoing with targeted completion third quarter 2002)
– 2 AESs
– 2 GESs - Ku band
– ATS/AOC application emulation
– EMS satellite
 Evaluation with airborne avionics and the participation of ATSPs
and airlines is in the planning stage
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Institutional aspects
EUROCONTROL
‘One Sky for Europe’
• Standardisation
 new satellite systems capability needs to be standardised for
worldwide operation
 confirm that NGSS SARPS are appropriate - seem so at initial
review
• Access control to space segment - who, how ?
• Use of AMS(R)S spectrum with many service providers
• GES operators
 detailed technical standards
 co-ordination between them e.g. use of codes, hand-overs, etc
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Business Issues
EUROCONTROL
‘One Sky for Europe’
• Technically SDLS looks possible but there is a need to
clarify business drivers
• Targeted at AMS(R)S therefore has to be paid by ATSPs
and airlines only e.g. no APC traffic
• However it is not vulnerable to market failure
• Benefits must come from cost saving
 ‘do nothing’ cases must be considered
 compare technology solutions
• Cost must be minimised
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Issues for further consideration
EUROCONTROL
‘One Sky for Europe’
• Data rate
 Lowest rate assumed acceptable - need to confirm (e.g. AOC)
• Use of Polling Service
 How is it used in practice ? Who controls the service and shares
the data ?
• Efficient use of satellite physical link
 need optimise the mapping of user data onto RF link
• ATSC voice service
 design of human interface for access
 party line acceptance
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Conclusions (1/3)
EUROCONTROL
‘One Sky for Europe’
• Satellite based communication system have advantages for
aviation
 wide coverage capability
 could overcome need for terrestrial infrastructure development in
some areas of the world
 traditionally thought of as oceanic and remote areas only but with
improved performance and lower cost can be considered for higher
density airspace
• Advanced design concepts seem to show that higher
service quality levels than AMSS are achievable with
proven technology
 can draw on AMSS experience and institutional arrangements
 ability to enable new service provision possibilities
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Conclusions (2/3)
EUROCONTROL
‘One Sky for Europe’
• Technical design concepts are well advanced in SDLS but
still open to refinement
 Finalisation of design in consultation with aviation community
• Institutional arrangements
 standards development - SARPS, MASPS, MOPS, etc
 can draw on NGSS work already undertaken
• Business case
 costs should be lower due to specific AMS(R)S goal
 better define the benefits including ‘do nothing ’ option
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)
Conclusions (3/3)
EUROCONTROL
‘One Sky for Europe’
• Recommendation on next steps in WG-C
 Contribute to the production of a global operating concept to
augment the ECAC Operational Concept
 Contribute to the development of a design definition document
 To liaise with AMCP WG-F to ensure the availability of adequate
AMS(R)S spectrum
 Address in due time the development of a Manual
© 2002 European Organisation for the Safety of Air Navigation (EUROCONTROL)