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VDL Mode 4VDL Mode 4Co-Site InvestigationsCo-Site Investigations
Part IPart ICo-Site Interference Co-Site Interference
ScenariosScenarios
Bertrand DESPERIERBertrand DESPERIER ISA TELECOMS ISA TELECOMS
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Problem Overview and Study Objectives
Characterize air co-site scenarios considered to be representative of real and anticipated operational cases
VDL Mode 4 & AM VDL Mode 4 & VDL Mode 2 Both point to point and broadcast VDL Mode 4 usage are addressed
Prepare the elaboration of detailed testing plan according to the identified scenarios
Explore operational quality of service requirements to identify related interference criteria
Interferer signal
Victim signal (from either air or ground)
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How to build a Scenario ?
Victim system User Profile: in time & size distribution (G/A or A/A) Received victim power
Interferer system User : in time & size distribution (A/G or A/A) Interferer power at the victim receiver input Frequency separation from victim channel
Interferer signal
Victim signal (from either air or ground)
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How to build a scenario ?
Airborne type :• Antenna coupling• Feeder Loss (Tx, Rx)• Co-site Interferer system power
Interferer Power @ victim receiver input
Spectrum:• ICAO FMG Frequency planning
Applications classes in use:• Broadcast• Point to point
Technologies properties:• Network overheads• Access Mode…
Interferer Channel occupancy profile
Victim Channel occupancy profile
Frequency Separation
Typical flight:• Flight phase• On event application triggering
Victim Power @ victim receiver input
Operational Scenario Testing Scenario
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Interferer Power
Interferer
Large Small Light
Same Opp. Same Opp. Same Opp.
Isolation (dB) 35 50 19 45 17 37
Rx Feeder loss (dB) 3 3 3
Total Losses (dB) -38 -53 -21 -49 -20 -40
Voice
Tx Power (dBm) 46 42 40
Interferer power at receiver input
(dBm)8 -7 21 -7 20 0
VDL4
Tx Power (dBm) 43 40 37
Interferer power at receiver input
(dBm)5 -10 18 14 17 -3
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Usage Profiles
AM profile are based on real data (Erctl voice profile study)
4 categories of Data Link profiles have been defined Ground to Air Surveillance broadcast (TIS-B) Air Surveillance broadcast (ADS-B) Sporadic point to point (CPDLC, CM, FIS, D-SIGMET,
NOTAM, FLIPCY,DYNAV …) Periodic point to point (ADS-C, CAP…)
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Minimum victim signal level
DSB-AMFrom ground
DSB-AMFrom air
VDL 4From ground
VDL 4From air
VDL 2From ground
Min signal at air receiver antenna
Annex 10, Vol. III
75 V/m-82 dBm
75 V/m-82 dBm
75 V/m-82 dBm
35 V/m-88 dBm
75 V/m-82 dBm
Feeder loss 3 dB 3 dB 3 dB 3 dB 3 dB
Antenna gain 0 dB 0 dB 0 dB 0 dB 0 dB
Minimum victim signal at receiver input
-85 dBm -85 dBm -85 dBm -91 dBm -85 dBm
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Spectrum
DSB-AM VDL4 VDL 2
VDL4(Assumed based on current VDL2
To be revisited )
4 Channels
100 kHz
1 Channel
25 kHz
VDL24 Channels
100 kHz
1 Channel
25 kHz
1 Channel
25 kHz
Current Required guard band