AMCP WGC5/WP6 REV1
AERONAUTICAL MOBILE COMMUNICATIONS PANEL (AMCP)
Working Group C – 5th meeting
Kobe, Japan
15 – 25 October 2002
Proposed new Chapter 11 of report to AMCP/8
Presented by Philippe Renaud
AMCP WGC5/WP6 REV1
11.0 Scenarios
Comments to: philippe.renaud@eurocontrol.int
This section identifies potential scenarios for the future communication infrastructure
balancing the investment already done, and adaptation of the systems to the services and
topologies.
The proposed scenarios are hereinafter illustrated by a temporal diagram describing how
the infrastructure would evolve in the next 15 years (around up to 2015). The diagrams
are accompanied with a description, the advantages and drawbacks identified as well as
the migration and the general issues
The proposed scenarios have been established in the light of analysis and validation
results and with the best knowledge of experts who feel them credible enough to be
proposed for consideration. However, it has to be highlighted that all the potential issues
have not yet been identified and therefore cleared for each of the proposed scenario.
Therefore, under identification of the preferred scenario(s), a careful identification of the
potential remaining issues and their clarification will need to be undertaken to be sure the
preferred scenario(s) meet all the ATM requirements before any final commitment
decision.
The scenario description is limited to high level considerations without going into details.
All scenarios assume implementation of ADS-B.
The number of scenarios has been limited to a minimum. However, some variants could
be added.
It has to be highlighted that a scenario will be viable only if the migration from the
current infrastructure to the next infrastructure is feasible without identified blocking
points. This is especially true considering that, during the overlapping period (which
could last for some time), systems (the system being withdrawn and the new system) have
to be simultaneously operated with consequences on spectrum availability for both
especially if they operate in the same band.
Another important aspect for the viability of a scenario is the economical aspect that
needs to be investigated and convincing.
General aspects for the scenario
Two main scenarios have been created (Scenario 1 and Scenario 2). They differ in types
of subnetworks which are considering different association of systems.
For each scenario, Voice and Data services are addressed separately (with a clear
distinction between Surveillance services and Communication).
Note: it has however to be noticed that, even if for editorial reasons, services are
presented separated, some systems may support several services, and integration of
service/supporting-systems could be amplified in the future.
For each scenario and for each service, four main regions are considered.
In the following description the scenarios are referred as “Scenario X - Y m” where:

“X” stands for the scenario:
 1 or
 2,
AMCP WGC5/WP6 REV1

“Y” stands for the service:
 V for Voice or,
 D” for Data
m stands for the area:
a Oceanic
b Low/medium traffic density regions where limited terrestrial communication
infrastructure exist
c Low/medium traffic density regions where largely terrestrial communication
infrastructure can be deployed
d High density (terrestrial) regions

Standardised ICAO systems
Standardised ICAO systems only locally available in the considered region
Not (yet) standardised ICAO systems
Note: colours have no special meaning
x
Trigger to operate an additional system
Meaning of the trigger:
• Capa: Increase of the telecommunication infrastructure capacity
• Qua: Improve the Quality of the voice exchanges
• Cov: Improve the coverage
• ATSAW: Air Traffic Situatin AWarness Datalink Service
• COSEP: COperative SEParation Datalink Service
• AUTOPS: AUTonomous OPerationS Datalink Service
• FANS 1: FANS 1 Datalink applications
• Build 1A: Build 1 and Build A Datalink applications
• Build 2: Build 2 Datalink applications
• ARINC 623: DCL/PDC and ATIS datalink applications character oriented
Terminal, airports & specific
Routes
Type of airspace where the system is supporting an ATS services
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SCENARIO 1
Scenario 1 - DESCRIPTION
This scenario is based on the extension of the 8.33 systems for voice services and, beyond
VDL Mode 2, on the introduction of VDL Mode 4 to support data communication services
and surveillance services in complement to Mode S extended Squitter and UAT which could
progressively replace Mode S extended squitter. In a more longer time frame further
improvements will be provided through the introduction of satellite-based system providing a
global service availability as well as through wide band system providing large capacity in the
terminal areas where a large traffic is expected.
Voice Communication services
In regions where it is not economically viable or feasible to implement a terrestrial-based
system (Scenario 1 - V a - e.g. oceanic, desert), voice communications will continue to be
based on long range systems i.e. current satellite system and HF. If there is requirement to
improve the voice quality or to decrease the operating cost, a new global voice satellite-based
system would be used.
In regions where the aeronautical traffic is low or medium and where it is economically viable
and feasible to install local (Scenario 1 - V b) or large-scale (Scenario 1 - V c) terrestrial
systems, the voice communications are supported by the VHF 25 kHz DSB-AM system, In
some areas, for reasons of voice quality and/or operating cost issues, a new satellite system
could progressively replace or complement the VHF DSB-AM systems.
In regions which experience congestion (Scenario 1 - V d), voice services will migrate to the
VHF 8.33 kHz DSB-AM system starting in the upper En-Route airspace and major TMAs
however avoiding any airspace where aircraft flies under VFR condition. Alternatively or in
complement (pending on its availability) satellite based services could be used to relax
congestion especially where the saturated systems are not spectrum efficient (e.g. the VHF in
the very upper airspace) as well as wide-band based technology in the terminal areas
Data Communication services
In the oceanic airspace, FANS1/A over AMSS will continue up to the availability of the new
satellite services supporting voice as well.
In region where the aeronautical traffic is low or medium and where it is economically viable
and feasible to install local (Scenario 1 - D b) or large-scale (Scenario 1 - D c) terrestrial
systems, VDL Mode 2 will provide services to support CPDLC Phase 1 services and CPDLC
Phase 2 services up to limit of the VDL mode 2 performance. When CPDLC Phase 2
requirements will not be met due to traffic increase, the scenario for High density regions
(Scenario 1 - D d) would apply.
In the high density (terrestrial) regions (Scenario 1 - D d), ARINC 623 services currently
supported over VHF/ACARS, will be migrated over AOA for spectrum efficiency. To support
CPDLC Phase 1 applications, full VDL Mode 2 services will continue to be provided. For the
introduction of CPDLC Phase 2 applications, VDL Mode 4 point-to-point capabilities will be
used. VDL Mode 4 will also support Build 1/A applications. The choice of the system by an
a/c will be on the basis of equipage.
To minimise the pressure on the VHF spectrum, new satellite systems and wide-band based
systems could be used to complement the terrestrial systems (Scenario 1 - D d). Satellite
systems could also be used in region with a non-existing or poor terrestrial infrastructure
(Scenario 1 - D a and 1 D b).
DATA surveillance services
AMCP WGC5/WP6 REV1
Surveillance ADS-B applications supporting ATSAW, COSEP and AUTOPS concept will be
provided over the Mode S extended squitter which progressively could be replaced by the
UAT, when the performance of Mode S ES is not sufficient. Mode S extended squitter will be
complemented with VDL Mode 4 broadcast services where Mode S does not meet all the
requirements.
Scenario 1 - V a
Voice Services
Oceanic Regions
Qua
New Satellite
Generation
AMSS
HF
Scenario 1 - V b
Voice Services
Low/medium traffic density regions where limited terrestrial
communication infrastructure exist
Cov, Qua
Except Terminal, airports &
specific Routes
Except Terminal, airports &
specific Routes
New Satellite
Generation
AMSS
Except Terminal, airports &
specific Routes
HF
Terminal, airports & specific
Routes
25 kHz DSB-AM
Scenario 1 - V c
Voice Services
Low/medium traffic density regions where largely terrestrial
communication infrastructure can be deployed
Qua
New Satellite
Generation
25 kHz DSB-AM
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Scenario 1 - V d
Voice Services
High density (terrestrial) Regions
Capa, Qua
Very upper En Route
New Satellite
Generation
Capa
En-Route and main terminal
VDL Mode 3
8.33 kHz DSB-AM
Upper En-Route airspace
Everywhere applicable
Lower En Route, Terminal &
airports
Minor Terminal
25 kHz DSB-AM
Capa, Qua
Wide Band
Reaching limit of capacity
Note: limits may not be reached at the same time in different regions (e.g. 1999 in Europe, 2009 in US)
Scenario 1 - D a
Terminal, airports
Data Services
Oceanic Regions
ATSAW, AUTOPS
MS Ext Sq
FANS 1/A
CPDLC Ph 1/2
New
Satellite Generation
AMSS
AMCP WGC5/WP6 REV1
Scenario 1 - D b
Data Services
Low/medium traffic density terrestrial regions where full terrestrial
communication infrastructure does not exist
ATSAW, COSEP, AUTOPS
MS Ext Sq
Cov, CPDLC Ph 1/2
New
Satellite Generation
Terminal, airports & specific
Routes
CPDLC Ph 1/2
VDL Mode 2
Scenario 1 - D c
Data Services
Low/medium traffic density terrestrial regions where full terrestrial
communication infrastructure exists
ATSAW, COSEP, AUTOPS
MS Ext Sq
CPDLC Ph 1/2
VDL Mode 2
AMCP WGC5/WP6 REV1
Scenario 1 - D d
Data Services
High density (terrestrial) Regions
ATSAW, COSEP
MS Ext Sq
+ VDL M4
Capa, CPDLC Ph 1
Complement of the terrestrial
CPDLC Ph 1
New Satellite
Generation
Arinc 623
CPDLC Ph 2
VDL Mode 4
ACARS
AOA
VDL Mode 2
Wide Band
Capa
Terminal, airports
Capa, CPDLC Ph 2
SCENARIO 1 - AVANTAGES/DRAWBACKS
While the communication infrastructure is improved by the introduction of better voice-quality systems
(new satellite replacing the poor voice quality HF system), this scenario shall challenge the critical onboard integration and the simultaneous operation of several VHF systems (2 mandatory radio
supporting voice, VDL Mode 2 radio, VDL Mode 4 radio to support ATN-ATC traffic and possibly
separate VDL Mode 4 radios to support ADS-B. The provision of Communication and Surveillance
services supporting critical functions (e.g. contributing to the aircraft separations) on the same
frequency band suffers from relying on the availability of the necessary VHF spectrum and on potential
safety issues (e.g. frequency jamming, single mode of failure).
SCENARIO 1 - MIGRATION
At the voice point of view, the infrastructure will offer two types of systems:

Systems operating in a broadcast mode with non-perceived establishment time and transit delay
i.e. VHF
AMCP WGC5/WP6 REV1

Systems requiring addressing function and with an establishment time and transit delay which
could be perceived by the operators (Pilots and Controller) i.e. HF, Satellite
This will involve modifications of the procedures when Air/Traffic Services will migrate from one
system to the next one. The pilots will experience different ways of operating different systems when
crossing between areas operating the two types of systems.
In the high traffic density regions, for data services, the migration feasibility will depend on the
sufficient spare VHF capacity supporting simultaneous operation of the “legacy” and of the newly
introduced systems during the transition phase which could last a long period.
SCENARIO 1 - ISSUES TO BE INVESTIGATED
• Multiple VHF systems to be integrated on-board (Analogue voice, VDL Mode 2, VDL Mode 4
for ADS-B, VDL Mode 4 for ATN) and to be operated simultaneously.
• On-board architecture and integration of multiple systems (multiple VHF systems, satellite, wide
band, and Mode S transponder and UAT).
• Suitability of the Extended Squitter to support the traffic expected beyond 2010
• Availability of the required VHF spectrum (including supporting legacy and new systems during
the transition phase)
• Operational consequences of voice systems with different system behaviours
• Operation of voice communication systems with perceivable transit and establishment time and
different addressing method
• Availability of satellite services at an affordable cost.
• Availability of spectrum to satisfy the VHF frequencies requirements to support the various
services and systems operating in the VHF band while considering the transition period during
which VDL Mode 2 and VDL Mode 4 will operate simultaneously requiring dedicated channels
for each system. Furthermore the consequence of the decision to accept or not to accommodate
on the same system and/or frequencies AOC and ATS traffic need to be assessed in term of
impact on spectrum availability.
AMCP WGC5/WP6 REV1
SCENARIO 2
Scenario 2 - DESCRIPTION
This scenario assumes the implementation of either VDL Mode 3 or 8.33, based on regional
decisions, for voice services and, beyond VDL Mode 2, on VDL Mode 3 for time critical
applications. To decrease the pressure on the VHF spectrum, as much as possible datalink
services will be supported over non-VHF systems (Mode S + UAT, L Band satellite)
Voice Communication services
In region where there is no capacity issue (Scenario 2 - V a, 2 - V b and 2 - V c), voice
communications will continue to be based on current systems (VHF and HF).
In regions which experience congestion (scenario 2 - V d), on regional choice, VHF 8.33 kHz
DSB-AM or VDL Mode 3 systems will be implemented. Deployment will start in the upper
En-Route airspace and major TMAs however avoiding any airspace where aircraft flies under
VFR condition. Note: for regions having implemented one of these systems, there is no
transition steps foreseen to migrate to the other system (e.g. implementing 8.33 then VDL
Mode 3) due to the difference in channelisation of both systems.
Data Communication services
In the oceanic airspace, FANS1/A over AMSS will continue up to the availability of the new
satellite services.
In region where the aeronautical traffic is low or medium and where it is economically viable
and feasible to install local (Scenario 2 - D b) or large-scale (Scenario 2 - D c) terrestrial
systems, VDL Mode 2 will provide services to support CPDLC Phase 1 services and CPDLC
Phase 2 services up to limit of performance of VDL Mode 2. Where VDL Mode 2 is not
uniformly deployed (scenario 2 - D b), VDL Mode 2 will be complemented by satellite
services.
When Build 2 requirements will not be met due to traffic increase, the scenario for High
density regions (Scenario 2 - D d) would apply.
In the high density (terrestrial) regions, ARINC 623 services currently supported over
VHF/ACARS service, will be migrated over AOA services for spectrum efficiency. To
support CPDLC Phase 1 applications, full DL Mode 2 services will be provided. For the
introduction of CPDLC Phase 2 applications, VDL Mode 3 will be deployed. For capacity
reason, the VDL systems will be complemented in the terminal areas (where large traffic is
expected) by wide band systems and by satellite system (which will ensure a global service
availability).
DATA surveillance services
Surveillance ADS-B applications supporting ATSAW, COSEP and AUTOPS concept will be
provided over the extended squitter of the Mode S. It will be complemented with UAT where
Mode S does not meet all the requirements.
AMCP WGC5/WP6 REV1
Scenario 2 - V a
Voice Services
Oceanic Regions
Qua
New Satellite
Generation
AMSS
HF
Scenario 2 - V b
Voice Services
Low/medium traffic density regions where limited terrestrial
communication infrastructure exist
Cov, Qua
Except Terminal, airports &
specific Routes
Except Terminal, airports &
specific Routes
New Satellite
Generation
AMSS
Except Terminal, airports &
specific Routes
HF
Terminal, airports & specific
Routes
25 kHz DSB-AM
Scenario 2 - V c
Voice Services
Low/medium traffic density regions where largely terrestrial
communication infrastructure can be deployed
Qua
New Satellite
Generation
25 kHz DSB-AM
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Scenario 2 - V d
Voice Services
High density (terrestrial) Regions
Capa, Qua
Very upper En Route
New Satellite
Generation
Regional decision
Capa
En-Route and main terminal
or
VDL Mode 3
Upper En-Route airspace
8.33 kHz DSB-AM
Everywhere applicable
Lower En Route, Terminal &
airports
Minor Terminal
25 kHz DSB-AM
Capa, Qua
Wide Band
Reaching limit of capacity
Terminal, airports
Note: limits may not be reached at the same time in different regions (e.g. 1999 in Europe, 2009 in US)
Scenario 2 - D a
Data Services
Oceanic Regions
ATSAW, AUTOPS
MS Ext Sq
FANS 1/A
CPDLC Ph 1/2
New
Satellite Generation
AMSS
AMCP WGC5/WP6 REV1
Scenario 2 - D b
Data Services
Low/medium traffic density terrestrial regions where full terrestrial
communication infrastructure does not exist
ATSAW, COSEP, AUTOPS
MS Ext Sq
Cov, CPDLC Ph 1/2
New
Satellite Generation
Terminal, airports & specific
Routes
CPDLC Ph 1/2
VDL Mode 2
Scenario 2 - D c
Data Services
Low/medium traffic density terrestrial regions where full terrestrial
communication infrastructure exists
ATSAW, COSEP, AUTOPS
MS Ext Sq
CPDLC Ph 1/2
VDL Mode 2
AMCP WGC5/WP6 REV1
Scenario 2 - D d
Data Services
High density (terrestrial) Regions
Capa
ATSAW, COSEP
MS Ext Sq
Capa, CPDLC Ph 2
UAT
Complement of the terrestrial
CPDLC Ph 1
Regional decision
Arinc 623
CPDLC Ph 2
New Satellite
Generation
and/or
VDL Mode 3
ACARS
AOA
VDL Mode 2
Wide Band
Capa
Terminal, airports
Capa, CPDLC Ph 2
SCENARIO 2 - AVANTAGES/DRAWBACKS
Scenario 2 minimises the pressure on VHF by operating non-VHF systems (mainly for data services)
and separates communication services and surveillance services over different spectrum bands
(avoiding single mode of failure in case of frequency jamming). However, several VHF systems shall
be integrated on-board (VHF DSB-AM, VDL Mode 2, VDL Mode 3 supporting voice and/or data
traffic), some of them being operated simultaneously. The voice quality in some region is not improved
(still provided over HF (quality) or AMSS (access time and delay)).
SCENARIO 2 - MIGRATION
At the voice point of view, the infrastructure will offer two types of systems:
• Systems operating in a broadcast mode with non-perceived establishment time and transit delay
(VHF)
• Systems requiring addressing function and with an establishment time and transit delay which
could be perceived by the operators (Pilots and Controller) - HF, Satellite
This will involve modifications of the procedures when Air/Traffic Services will migrate from one
system to the next one. The pilots will also experience different ways of operating different systems
when crossing between areas operating the two types of systems.
For the transition between the VHF systems, sufficient spare spectrum capacity will have to be made
available to ensure simultaneous operation of the “legacy” and the newly-introduced systems during
the transition phase (which could last a long period).
AMCP WGC5/WP6 REV1
SCENARIO 2 - ISSUES TO BE INVESTIGATED
• Multiple VHF systems to be integrated on-board (Analogue voice, VDL Mode 2, VDL Mode 3)
with combinations of these systems to be operated simultaneously.
• On-board integration of multiple systems (Voice, VDL Mode 2, VDL Mode 3,Extended Squitter,
UAT, wide band, satellite).
• Availability of the required VHF spectrum (supporting legacy and new systems during the
transition phase)
• Suitability of VDL Mode 3 to meet the expected datalink requirements
• Suitability of the Extended Squitter to support the traffic expected beyond 2010
• Operational consequences of voice systems with different system behaviours
• Operation of voice communication systems with perceivable transit and establishment time and
different addressing method
• Availability of satellite services at an affordable cost.
• Clarification of the voice communications (2) and data VDL Mode 3 and VDL Mode 2 links to
be established at the same time (VDL Mode 2 being assumed to be operated for a long time at
least for AOC) and consequence on the airborne architecture and on the management of the
communications (and the impact on number of simultaneous frequencies required).
Migration of VDL Mode 2 to VDL Mode 3 (Business case for Service Providers vis-à-vis Mode 3 for
AOC).