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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